Chuyển tới nội dung
Number Buffet
vi

500 số dư thừa đầu tiên

12, 18, 20, 24, 30, 36, 40, 42, 48, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100, 102, 104, 108, 112, 114, 120, 126, 132, 138, 140, 144, 150, 156, 160, 162, 168, 174, 176, 180, 186, 192, 196, 198, 200, 204, 208, 210, 216, 220, 222, 224, 228, 234, 240, 246, 252, 258, 260, 264, 270, 272, 276, 280, 282, 288, 294, 300, 304, 306, 308, 312, 318, 320, 324, 330, 336, 340, 342, 348, 350, 352, 354, 360, 364, 366, 368, 372, 378, 380, 384, 390, 392, 396, 400, 402, 408, 414, 416, 420, 426, 432, 438, 440, 444, 448, 450, 456, 460, 462, 464, 468, 474, 476, 480, 486, 490, 492, 498, 500, 504, 510, 516, 520, 522, 528, 532, 534, 540, 544, 546, 550, 552, 558, 560, 564, 570, 572, 576, 580, 582, 588, 594, 600, 606, 608, 612, 616, 618, 620, 624, 630, 636, 640, 642, 644, 648, 650, 654, 660, 666, 672, 678, 680, 684, 690, 696, 700, 702, 704, 708, 714, 720, 726, 728, 732, 736, 738, 740, 744, 748, 750, 756, 760, 762, 768, 770, 774, 780, 784, 786, 792, 798, 800, 804, 810, 812, 816, 820, 822, 828, 832, 834, 836, 840, 846, 852, 858, 860, 864, 868, 870, 876, 880, 882, 888, 894, 896, 900, 906, 910, 912, 918, 920, 924, 928, 930, 936, 940, 942, 945, 948, 952, 954, 960, 966, 968, 972, 978, 980, 984, 990, 992, 996, 1,000, 1,002, 1,008, 1,014, 1,020, 1,026, 1,032, 1,036, 1,038, 1,040, 1,044, 1,050, 1,056, 1,060, 1,062, 1,064, 1,068, 1,074, 1,080, 1,086, 1,088, 1,092, 1,098, 1,100, 1,104, 1,110, 1,116, 1,120, 1,122, 1,128, 1,134, 1,140, 1,144, 1,146, 1,148, 1,152, 1,158, 1,160, 1,164, 1,170, 1,176, 1,180, 1,182, 1,184, 1,188, 1,190, 1,194, 1,200, 1,204, 1,206, 1,212, 1,216, 1,218, 1,220, 1,224, 1,230, 1,232, 1,236, 1,240, 1,242, 1,248, 1,254, 1,260, 1,266, 1,272, 1,278, 1,280, 1,284, 1,288, 1,290, 1,296, 1,300, 1,302, 1,308, 1,312, 1,314, 1,316, 1,320, 1,326, 1,330, 1,332, 1,338, 1,340, 1,344, 1,350, 1,352, 1,356, 1,360, 1,362, 1,368, 1,372, 1,374, 1,376, 1,380, 1,386, 1,392, 1,398, 1,400, 1,404, 1,408, 1,410, 1,416, 1,420, 1,422, 1,428, 1,430, 1,434, 1,440, 1,446, 1,452, 1,456, 1,458, 1,460, 1,464, 1,470, 1,472, 1,476, 1,480, 1,482, 1,484, 1,488, 1,494, 1,496, 1,500, 1,504, 1,506, 1,512, 1,518, 1,520, 1,524, 1,530, 1,536, 1,540, 1,542, 1,548, 1,554, 1,560, 1,566, 1,568, 1,572, 1,575, 1,578, 1,580, 1,584, 1,590, 1,596, 1,600, 1,602, 1,608, 1,610, 1,614, 1,620, 1,624, 1,626, 1,632, 1,638, 1,640, 1,644, 1,650, 1,652, 1,656, 1,660, 1,662, 1,664, 1,668, 1,672, 1,674, 1,680, 1,686, 1,692, 1,696, 1,698, 1,700, 1,704, 1,708, 1,710, 1,716, 1,720, 1,722, 1,728, 1,734, 1,736, 1,740, 1,746, 1,750, 1,752, 1,758, 1,760, 1,764, 1,768, 1,770, 1,776, 1,780, 1,782, 1,788, 1,792, 1,794, 1,800, 1,806, 1,812, 1,818, 1,820, 1,824, 1,830, 1,836, 1,840, 1,842, 1,848, 1,854, 1,856, 1,860, 1,866, 1,870, 1,872, 1,876, 1,878, 1,880, 1,884, 1,888, 1,890, 1,896, 1,900, 1,902, 1,904, 1,908, 1,914, 1,920, 1,926, 1,932, 1,936, 1,938, 1,940, 1,944, 1,950, 1,952, 1,956, 1,960, 1,962, 1,968, 1,974, 1,976, 1,980, 1,984, 1,986, 1,988, 1,992, 1,998, 2,000, 2,002, 2,004, 2,010, 2,016, 2,020, 2,022, 2,024

Thiết lập

Thiết lập nhanh

Used in count mode. Terms are produced in ascending order from 12, the smallest abundant number.

Used in range mode. Inclusive.

Used in range mode. Inclusive, up to 4,000,000.

Appends σ(n) − 2n, the amount by which the divisors overshoot. 12 overshoots by 4.

Tinh chỉnh dáng vẻ

Hãy chọn một thiết lập cạnh ảnh trước — các điều khiển này điều chỉnh nó.

Frame

A border drawn inside the edge of the image.

Nâng cao

Kết quả

500 giá trị

12, 18, 20, 24, 30, 36, 40, 42, 48, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100, 102, 104, 108, 112, 114, 120, 126, 132, 138, 140, 144, 150, 156, 160, 162, 168, 174, 176, 180, 186, 192, 196, 198, 200, 204, 208, 210, 216, 220, 222, 224, 228, 234, 240, 246, 252, 258, 260, 264, 270, 272, 276, 280, 282, 288, 294, 300, 304, 306, 308, 312, 318, 320, 324, 330, 336, 340, 342, 348, 350, 352, 354, 360, 364, 366, 368, 372, 378, 380, 384, 390, 392, 396, 400, 402, 408, 414, 416, 420, 426, 432, 438, 440, 444, 448, 450, 456, 460, 462, 464, 468, 474, 476, 480, 486, 490, 492, 498, 500, 504, 510, 516, 520, 522, 528, 532, 534, 540, 544, 546, 550, 552, 558, 560, 564, 570, 572, 576, 580, 582, 588, 594, 600, 606, 608, 612, 616, 618, 620, 624, 630, 636, 640, 642, 644, 648, 650, 654, 660, 666, 672, 678, 680, 684, 690, 696, 700, 702, 704, 708, 714, 720, 726, 728, 732, 736, 738, 740, 744, 748, 750, 756, 760, 762, 768, 770, 774, 780, 784, 786, 792, 798, 800, 804, 810, 812, 816, 820, 822, 828, 832, 834, 836, 840, 846, 852, 858, 860, 864, 868, 870, 876, 880, 882, 888, 894, 896, 900, 906, 910, 912, 918, 920, 924, 928, 930, 936, 940, 942, 945, 948, 952, 954, 960, 966, 968, 972, 978, 980, 984, 990, 992, 996, 1,000, 1,002, 1,008, 1,014, 1,020, 1,026, 1,032, 1,036, 1,038, 1,040, 1,044, 1,050, 1,056, 1,060, 1,062, 1,064, 1,068, 1,074, 1,080, 1,086, 1,088, 1,092, 1,098, 1,100, 1,104, 1,110, 1,116, 1,120, 1,122, 1,128, 1,134, 1,140, 1,144, 1,146, 1,148, 1,152, 1,158, 1,160, 1,164, 1,170, 1,176, 1,180, 1,182, 1,184, 1,188, 1,190, 1,194, 1,200, 1,204, 1,206, 1,212, 1,216, 1,218, 1,220, 1,224, 1,230, 1,232, 1,236, 1,240, 1,242, 1,248, 1,254, 1,260, 1,266, 1,272, 1,278, 1,280, 1,284, 1,288, 1,290, 1,296, 1,300, 1,302, 1,308, 1,312, 1,314, 1,316, 1,320, 1,326, 1,330, 1,332, 1,338, 1,340, 1,344, 1,350, 1,352, 1,356, 1,360, 1,362, 1,368, 1,372, 1,374, 1,376, 1,380, 1,386, 1,392, 1,398, 1,400, 1,404, 1,408, 1,410, 1,416, 1,420, 1,422, 1,428, 1,430, 1,434, 1,440, 1,446, 1,452, 1,456, 1,458, 1,460, 1,464, 1,470, 1,472, 1,476, 1,480, 1,482, 1,484, 1,488, 1,494, 1,496, 1,500, 1,504, 1,506, 1,512, 1,518, 1,520, 1,524, 1,530, 1,536, 1,540, 1,542, 1,548, 1,554, 1,560, 1,566, 1,568, 1,572, 1,575, 1,578, 1,580, 1,584, 1,590, 1,596, 1,600, 1,602, 1,608, 1,610, 1,614, 1,620, 1,624, 1,626, 1,632, 1,638, 1,640, 1,644, 1,650, 1,652, 1,656, 1,660, 1,662, 1,664, 1,668, 1,672, 1,674, 1,680, 1,686, 1,692, 1,696, 1,698, 1,700, 1,704, 1,708, 1,710, 1,716, 1,720, 1,722, 1,728, 1,734, 1,736, 1,740, 1,746, 1,750, 1,752, 1,758, 1,760, 1,764, 1,768, 1,770, 1,776, 1,780, 1,782, 1,788, 1,792, 1,794, 1,800, 1,806, 1,812, 1,818, 1,820, 1,824, 1,830, 1,836, 1,840, 1,842, 1,848, 1,854, 1,856, 1,860, 1,866, 1,870, 1,872, 1,876, 1,878, 1,880, 1,884, 1,888, 1,890, 1,896, 1,900, 1,902, 1,904, 1,908, 1,914, 1,920, 1,926, 1,932, 1,936, 1,938, 1,940, 1,944, 1,950, 1,952, 1,956, 1,960, 1,962, 1,968, 1,974, 1,976, 1,980, 1,984, 1,986, 1,988, 1,992, 1,998, 2,000, 2,002, 2,004, 2,010, 2,016, 2,020, 2,022, 2,024

Tạo ảnh

Hãy bật JavaScript để tạo kiểu cho những số này và tải về dưới dạng ảnh. Bản thân các giá trị đã được liệt kê ở trên.

Text on the image

Drag a line straight onto the picture to place it — once placed, it stays exactly where you put it. Everything here is drawn into the download.

500 số dư thừa đầu tiên là những số nào?

500 số dư thừa đầu tiên là:

12, 18, 20, 24, 30, 36, 40, 42, 48, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100, 102, 104, 108, 112, 114, 120, 126, 132, 138, 140, 144, 150, 156, 160, 162, 168, 174, 176, 180, 186, 192, 196, 198, 200, 204, 208, 210, 216, 220, 222, 224, 228, 234, 240, 246, 252, 258, 260, 264, 270, 272, 276, 280, 282, 288, 294, 300, 304, 306, 308, 312, 318, 320, 324, 330, 336, 340, 342, 348, 350, 352, 354, 360, 364, 366, 368, 372, 378, 380, 384, 390, 392, 396, 400, 402, 408, 414, 416, 420, 426, 432, 438, 440, 444, 448, 450, 456, 460, 462, 464, 468, 474, 476, 480, 486, 490, 492, 498, 500, 504, 510, 516, 520, 522, 528, 532, 534, 540, 544, 546, 550, 552, 558, 560, 564, 570, 572, 576, 580, 582, 588, 594, 600, 606, 608, 612, 616, 618, 620, 624, 630, 636, 640, 642, 644, 648, 650, 654, 660, 666, 672, 678, 680, 684, 690, 696, 700, 702, 704, 708, 714, 720, 726, 728, 732, 736, 738, 740, 744, 748, 750, 756, 760, 762, 768, 770, 774, 780, 784, 786, 792, 798, 800, 804, 810, 812, 816, 820, 822, 828, 832, 834, 836, 840, 846, 852, 858, 860, 864, 868, 870, 876, 880, 882, 888, 894, 896, 900, 906, 910, 912, 918, 920, 924, 928, 930, 936, 940, 942, 945, 948, 952, 954, 960, 966, 968, 972, 978, 980, 984, 990, 992, 996, 1,000, 1,002, 1,008, 1,014, 1,020, 1,026, 1,032, 1,036, 1,038, 1,040, 1,044, 1,050, 1,056, 1,060, 1,062, 1,064, 1,068, 1,074, 1,080, 1,086, 1,088, 1,092, 1,098, 1,100, 1,104, 1,110, 1,116, 1,120, 1,122, 1,128, 1,134, 1,140, 1,144, 1,146, 1,148, 1,152, 1,158, 1,160, 1,164, 1,170, 1,176, 1,180, 1,182, 1,184, 1,188, 1,190, 1,194, 1,200, 1,204, 1,206, 1,212, 1,216, 1,218, 1,220, 1,224, 1,230, 1,232, 1,236, 1,240, 1,242, 1,248, 1,254, 1,260, 1,266, 1,272, 1,278, 1,280, 1,284, 1,288, 1,290, 1,296, 1,300, 1,302, 1,308, 1,312, 1,314, 1,316, 1,320, 1,326, 1,330, 1,332, 1,338, 1,340, 1,344, 1,350, 1,352, 1,356, 1,360, 1,362, 1,368, 1,372, 1,374, 1,376, 1,380, 1,386, 1,392, 1,398, 1,400, 1,404, 1,408, 1,410, 1,416, 1,420, 1,422, 1,428, 1,430, 1,434, 1,440, 1,446, 1,452, 1,456, 1,458, 1,460, 1,464, 1,470, 1,472, 1,476, 1,480, 1,482, 1,484, 1,488, 1,494, 1,496, 1,500, 1,504, 1,506, 1,512, 1,518, 1,520, 1,524, 1,530, 1,536, 1,540, 1,542, 1,548, 1,554, 1,560, 1,566, 1,568, 1,572, 1,575, 1,578, 1,580, 1,584, 1,590, 1,596, 1,600, 1,602, 1,608, 1,610, 1,614, 1,620, 1,624, 1,626, 1,632, 1,638, 1,640, 1,644, 1,650, 1,652, 1,656, 1,660, 1,662, 1,664, 1,668, 1,672, 1,674, 1,680, 1,686, 1,692, 1,696, 1,698, 1,700, 1,704, 1,708, 1,710, 1,716, 1,720, 1,722, 1,728, 1,734, 1,736, 1,740, 1,746, 1,750, 1,752, 1,758, 1,760, 1,764, 1,768, 1,770, 1,776, 1,780, 1,782, 1,788, 1,792, 1,794, 1,800, 1,806, 1,812, 1,818, 1,820, 1,824, 1,830, 1,836, 1,840, 1,842, 1,848, 1,854, 1,856, 1,860, 1,866, 1,870, 1,872, 1,876, 1,878, 1,880, 1,884, 1,888, 1,890, 1,896, 1,900, 1,902, 1,904, 1,908, 1,914, 1,920, 1,926, 1,932, 1,936, 1,938, 1,940, 1,944, 1,950, 1,952, 1,956, 1,960, 1,962, 1,968, 1,974, 1,976, 1,980, 1,984, 1,986, 1,988, 1,992, 1,998, 2,000, 2,002, 2,004, 2,010, 2,016, 2,020, 2,022, 2,024

Bài viết nền bên dưới chưa được dịch và đang hiển thị bằng tiếng Anh.

Về số dư thừa

The three-way split of the integers into abundant, perfect and deficient comes from Nicomachus of Gerasa, who set it out in his Introduction to Arithmetic around 100 CE. Nicomachus was writing a Pythagorean textbook rather than doing arithmetic for its own sake, and he presented the classification as a moral taxonomy: a number whose divisors overshoot it he described in the language of bodily excess — too many fingers, too many limbs — while deficiency was a lack and perfection the virtuous mean between them. The arithmetic held up even where the metaphor did not. The proper divisors of 12 are 1, 2, 3, 4 and 6; they total 16, so 12 is the smallest abundant number.

Boethius translated Nicomachus into Latin around 500 CE in De institutione arithmetica, and it is his vocabulary — numerus abundans, numerus deficiens — that English eventually inherited. Because that work was a set text of the medieval quadrivium, the classification was taught across Europe for roughly a thousand years, and the moral framing travelled with it.

Quantitative results came much later, once the question became statistical rather than definitional. Harold Davenport showed in 1933 that the abundancy index σ(n)/n has a continuous distribution function, which is what makes it meaningful to speak of the proportion of integers that are abundant at all. Marc Deléglise computed that proportion in 1998, pinning it between 0.2474 and 0.2480.

The modern interest in extreme abundance is sharper still. Leonidas Alaoglu and Paul Erdős named the superabundant numbers in 1944 — those more abundant than anything smaller — and in 1984 Guy Robin proved that the Riemann hypothesis is equivalent to a single inequality bounding σ(n) for every n above 5040. How far abundance can go turns out to be one of the central open questions in mathematics.

Tính chất chính

  • A number is abundant when its proper divisors sum to more than itself, equivalently σ(n) > 2n. The smallest is 12, because 1 + 2 + 3 + 4 + 6 = 16.
  • The smallest odd abundant number is 945 = 3³ × 5 × 7. Every odd number below 945 is deficient.
  • Every multiple of an abundant number is abundant, and every proper multiple of a perfect number is abundant — so there are infinitely many.
  • Abundant numbers have a natural density: Marc Deléglise showed in 1998 that it lies between 0.2474 and 0.2480, so close to one integer in four is abundant.
  • Odd abundant numbers are far rarer than even ones: there are 23 below ten thousand and 1,996 below one million.
  • 20161 is the largest integer that cannot be written as the sum of two abundant numbers; every larger integer can.
  • An abundant number whose proper divisors are all deficient is called primitive abundant. The smallest is 20.
  • No number with σ(n) = 2n + 1 — abundant by exactly one, a "quasiperfect" number — has ever been found, and whether any exists is open.

Số lượng khác

Nguồn