A039929 Second column of Fibonacci Jabotinsky-triangle A039692.

0, 1, 9, 59, 450, 4114, 43512, 528492, 7235568, 110499696, 1862118720, 34342356960, 688092312960, 14886351037440, 345878769358080, 8590707803462400, 227153424885811200, 6371121297516595200

Offset

1,3

Comments

E.g.f.: (log(1-x-x^2))^2/2.

Links

Table of n, a(n) for n=1..18.

Formula

a(n) = A039692(n, 2); a(n) = (n-1)!*sum(L(j)*L(n-j)/(n-j), j=1..n-1), n >= 2, L(n)= A000032(n) (Lucas).

Mathematica

With[{nn=20}, CoefficientList[Series[Log[1-x-x^2]^2/2, {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jun 11 2017 *)

Crossrefs

Cf. A039692, A039647, A000032, A005442.

Sequence in context: A231228 A198847 A059356 * A099333 A098327 A118674

Adjacent sequences: A039926 A039927 A039928 * A039930 A039931 A039932

Keyword

easy,nonn

Author

Wolfdieter Lang

Status

approved