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Search: id:A119771
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| A119771 |
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Product of n^2 and n-th tetrahedral number: n^3*(n+1)*(n+2)/6. |
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+0
2
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| 0, 1, 16, 90, 320, 875, 2016, 4116, 7680, 13365, 22000, 34606, 52416, 76895, 109760, 153000, 208896, 280041, 369360, 480130, 616000, 781011, 979616, 1216700, 1497600, 1828125, 2214576, 2663766, 3183040, 3780295, 4464000, 5243216
(list; graph; listen)
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OFFSET
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0,3
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COMMENT
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If n is divisible by 10, then a(n) is divisible by 1000
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EXAMPLE
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a(25) = n^3*(n+1)*(n+2)/6 = 25^3*(25+1)*(25+2)/6 = 15625*26*27/6 = 15625*13*9 = 1,828,125.
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MAPLE
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with(combinat):a:=n->sum(sum(sum(binomial(n+2, 2)/3, j=1..n), k=1..n), m=1..n): seq(a(n), n=0..31); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 30 2007
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CROSSREFS
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Cf. A000290, A000292.
Sequence in context: A022676 A035291 A120045 this_sequence A055920 A055856 A050406
Adjacent sequences: A119768 A119769 A119770 this_sequence A119772 A119773 A119774
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KEYWORD
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easy,nonn
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AUTHOR
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Brandon Ang (xyz1236(AT)verizon.net), Jun 28 2006
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