A371311 Expansion of e.g.f. Product_{k>=1} (1 + k*x^k/(k-1)!).

1, 1, 4, 21, 52, 465, 3306, 14161, 74208, 960777, 10558630, 44851521, 361716576, 2473446157, 46951741760, 735722365995, 3502764883456, 27660533205537, 257573937401838, 2415069153393553, 62591287234200960, 1356650271603527061, 6966660193683272104, 61046400429116180475

Offset: 0

Author

Ilya Gutkovskiy, Mar 24 2024

Keywords

• nonn

Comments

"EFJ" (unordered, size, labeled) transform of squares.

Links

• C. G. Bower, Transforms (2)

Crossrefs

Cf. A000290, A007837, A032299, A032300, A092484.

Programs

Mathematica

nmax = 23; CoefficientList[Series[Product[(1 + k x^k/(k - 1)!), {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!