A259326 Ceiling of ((2^n)!+(2^n-1)^2*(2^(n-1))!*2^(2^(n-1)))/(4^n*(n!)^2).

1, 2, 26, 141907500, 17844701940490373256193966080, 59757436204078657410908164193971177467473348779378572774972093904092502425600000

Offset

1,2

Links

Table of n, a(n) for n=1..6.

C. S. Lorens, Invertible Boolean functions, IEEE Trans. Electron. Computers, EC-13 (1964), 529-541.

C. S. Lorens, Invertible Boolean functions, IEEE Trans. Electron. Computers, EC-13 (1964), 529-541. [Annotated scan of page 530 only]

Maple

# Maple code for A259326, A259327, A259328, A259329, A259330, A259331:
f:=n->((2^n)!+(2^n-1)^2*(2^(n-1))!*2^(2^(n-1)))/(4^n*(n!)^2);
f:=n->((2^n)!)/(4^n*(n!)^2);
f:=n->((2^n)!)/(2^(n*(n-1))*mul((2^i-1)^2, i=1..n));
f:=n->((2^n)!)/(4^(n^2));
f:=n->((2^n)!)/(2^(n*(n+1))*mul((2^i-1)^2, i=1..n));
f:=n->((2^n)!)/(4^n*2^(2*n^2));
[seq(ceil(f(n)), n=1..6)];

Crossrefs

Cf. A259327, A259328, A259329, A259330, A259331.

Sequence in context: A330032 A273381 A094680 * A061192 A356136 A370497

Adjacent sequences: A259323 A259324 A259325 * A259327 A259328 A259329

Keyword

nonn

Author

N. J. A. Sloane, Jun 24 2015

Status

approved