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A013127
Expansion of e.g.f.: sec(tanh(x)+log(x+1))=1+4/2!*x^2-6/3!*x^3+83/4!*x^4-460/5!*x^5...
0
1, 0, 4, -6, 83, -460, 5374, -52962, 711833, -9731160, 156311784, -2676262710, 50867352939, -1037096208564, 22896291533210, -539916293280210, 13603842760270129, -363832977079307248, 10308592491205055532
OFFSET
0,3
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Sec[Tanh[x]+Log[x+1]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Feb 27 2023 *)
CROSSREFS
Sequence in context: A375660 A303211 A264374 * A012970 A196814 A213335
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Definition clarified by Harvey P. Dale, Feb 27 2023
STATUS
approved