A265084 Column 4 of array in A265080.

0, 4, 20, 108, 544, 2540, 11544, 52192, 231872, 1014444, 4401400, 19016888, 81588720, 347833408, 1476460496, 6250982640, 26366866432, 110825294252, 464575219704, 1944165731800, 8117172816560, 33813868882584, 140605002878032, 583960731640688, 2421457649730528, 10025040350809600

Offset: 0

Author

N. J. A. Sloane, Jan 01 2016

Keywords

• nonn

Links

• Andrew Howroyd, Table of n, a(n) for n = 0..500
• D. R. L. Brown, Bounds on surmising remixed keys, IACR, Report 2015/375, 2015-2016. See Table 1.

Crossrefs

Cf. A265080.

Programs

PARI

seq(n)={Vec(serlaplace(sum(j=0, n, exp(4*x + O(x*x^n)) - sum(i=0, j, x^i/i!, O(x*x^n))^4)), -n-1)} \\ Andrew Howroyd, Aug 09 2025

Formula

E.g.f.: Sum_{j>=0} (exp(x)^4 - (Sum_{i=0..j} x^i/i!)^4). - Andrew Howroyd, Aug 09 2025

Extensions

a(6) onwards from Andrew Howroyd, Aug 09 2025