A270665 E.g.f.: Product_{k>=1} 1/(1 - tan(x^k)).

1, 1, 4, 20, 136, 1016, 10112, 102080, 1259648, 16501888, 243214592, 3792156928, 66314635264, 1201731751936, 23824296632320, 496708324364288, 11065302289285120, 257749924759273472, 6397599337673523200, 165009476729535463424, 4496775223731602063360

Offset

0,3

Links

Table of n, a(n) for n=0..20.

Mathematica

nmax = 25; Range[0, nmax]! * CoefficientList[Series[Product[1/(1-Tan[x^k]), {k, 1, nmax}], {x, 0, nmax}], x]

Crossrefs

Cf. A203716, A218504, A270664, A270666.

Sequence in context: A360660 A143463 A290444 * A330538 A141716 A129102

Adjacent sequences: A270662 A270663 A270664 * A270666 A270667 A270668

Keyword

nonn

Author

Vaclav Kotesovec, Mar 21 2016

Status

approved