A185968 - OEIS

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A185968

a(n) = n^2*2^(n^2-1).

0, 1, 32, 2304, 524288, 419430400, 1236950581248, 13792273858822144, 590295810358705651712, 97922991388784963151200256, 63382530011411470074835160268800

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OFFSET

0,3

COMMENTS

a(n) is the number of elements (ordered pairs) in all binary relations on {1,2,...,n}.

Equivalently a(n) is the number of 1's in all n X n {0,1} matrices.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..57

MATHEMATICA

Table[n^2 *2^(n^2-1), {n, 0, 10}]

PROG

(PARI) for(n=0, 25, print1(n^2 *2^(n^2-1), ", ")) \\ G. C. Greubel, Jul 23 2017