A085741 a(n) = T(n)^n, where T() are the triangular numbers (A000217).
1, 1, 9, 216, 10000, 759375, 85766121, 13492928512, 2821109907456, 756680642578125, 253295162119140625, 103510234140112521216, 50714860157241037295616, 29345269354638035222576971
Offset: 0
Examples
a(3) = T(3)^3 = 6^3 = 216.
Links
- Vincenzo Librandi, Table of n, a(n) for n = 0..200
Programs
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Magma
[((n*(n+1))/2)^n: n in [0..20]]; // Vincenzo Librandi, Sep 14 2011
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Maple
a:=n->mul(sum(j, j=1..n),k=1..n): seq(a(n), n=0..13); # Zerinvary Lajos, Jun 02 2007
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Mathematica
With[{rnn=Range[20]},Join[{1},First[#]^Last[#]&/@Thread[ {Accumulate[ rnn], rnn}]]] (* Harvey P. Dale, Dec 08 2013 *) -
PARI
a(n) = (n*(n+1)/2)^n; \\ Michel Marcus, Feb 19 2019
Formula
a(n) = ((n*(n+1))/2)^n. - Vincenzo Librandi, Sep 14 2011
Extensions
More terms from Ray Chandler, Nov 09 2003