A302686 a(n) = [x^n] 1 + x*(1 + x*(1 + x*(1 + x*(1 + ...)^(4*n))^(3*n))^(2*n))^n.

1, 1, 2, 21, 596, 32805, 2960496, 396523540, 73803150440, 18216533196693, 5757491981210470, 2267526164705341925, 1088820552191787545688, 626169526288460672060244, 424903177461959840892846066, 335946105815409394263421836000, 306145042287138023678922165314512

Offset

0,3

Links

Table of n, a(n) for n=0..16.

Mathematica

Table[SeriesCoefficient[1 + x Fold[(x #1 + 1)^(n #2) &, 0, Reverse[Range[n]]], {x, 0, n}], {n, 0, 16}]

Crossrefs

Cf. A095793, A138212, A138213, A138214, A138215, A138216, A302657.

Sequence in context: A218768 A195736 A320653 * A078602 A060319 A095224

Adjacent sequences: A302683 A302684 A302685 * A302687 A302688 A302689

Keyword

nonn

Author

Ilya Gutkovskiy, Apr 11 2018

Status

approved