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%I #8 Aug 19 2016 00:39:48
%S 2,4,19,181,2701,56701,1587601,57153601,2571912001,141455160001,
%T 9336040560001,728211163680001,66267215894880001,6958057668962400001,
%U 834966920275488000001,113555501157466368000001
%N a(n) = product of first n triangular numbers (A000217) + 1.
%H Harry J. Smith, <a href="/A061213/b061213.txt">Table of n, a(n) for n=1,...,100</a>
%F a(n) = {n(n+1)/2}*{a(n-1)-1}+1
%e a(6) = 1 * 3 * 6 * 10 *15 * 21 + 1 = 56701
%p for n from 1 to 30 do printf(`%d,`,1+product(j*(j+1)/2, j=1..n)) od:
%o (PARI) { for (n=1, 100, if (n>1, a=(n*(n + 1)/2)*(a - 1) + 1, a=2); write("b061213.txt", n, " ", a) ) } \\ _Harry J. Smith_, Jul 19 2009
%Y Equals A006472 + 1.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Apr 21 2001
%E More terms from _James A. Sellers_, Apr 24 2001
%E OFFSET changed from 0,1 to 1,1 and EXAMPLE corrected by _Harry J. Smith_, Jul 19 2009
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