login
A270598
E.g.f.: Product_{k>0} (1 + tanh(x^k/k)).
7
1, 1, 1, 3, 14, 70, 364, 2548, 21104, 189936, 1830968, 20140648, 241712272, 3142259536, 43472528384, 652087925760, 10396900456448, 176747307759616, 3162885135453952, 60094817573625088, 1198006583353972736, 25158138250433427456, 551506339507727783936
OFFSET
0,4
LINKS
FORMULA
E.g.f.: Product_{k>0} exp(x^k/k)/cosh(x^k/k).
a(n) ~ c * n!, where c = 1/A249673 = 1/Product_{k>=1} cosh(1/k) = 0.472485841489...
MATHEMATICA
nn=25; Range[0, nn]! * CoefficientList[Series[Product[1+Tanh[x^k/k], {k, 1, nn}], {x, 0, nn}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Mar 20 2016
STATUS
approved