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Search: id:A110771
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| A110771 |
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The r-th term of the n-th row of the following triangle is C[{T(n)-T(r-1)},r] where T(n) is the n-th triangular number. 1 3 1 6 10 1 10 36 35 1 ... Sequence contains the row sums. |
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+0
2
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| 1, 4, 17, 82, 453, 2855, 20279, 159972, 1383544, 12987671, 131301747, 1420538383, 16358806638, 199606632428, 2570446661320, 34814885202341, 494470158654963, 7344794248474716, 113829232686474480
(list; graph; listen)
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OFFSET
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1,2
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COMMENT
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The first term is T(n), the n-th term is 1.
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EXAMPLE
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For n = 4 the terms of the 4-th row are C(10,1), C(9,2),C(7,3), C(4,4). 10,36,35,1 and the sum is a(4) = 82.
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MATHEMATICA
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A110771[n_] := Plus @@ Table[Binomial[Binomial[n + 1, 2] - Binomial[r, 2], r], {r, 1, n}]; Table[A110771[i], {i, 1, 25}]
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CROSSREFS
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Cf. A110768, A110769, A110770.
Sequence in context: A151250 A121545 A078845 this_sequence A082028 A052315 A093904
Adjacent sequences: A110768 A110769 A110770 this_sequence A110772 A110773 A110774
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KEYWORD
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easy,nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Aug 12 2005
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EXTENSIONS
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More terms and Mathematica program from Keith Schneider, Jul 03 2007
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