1436473

Appears in sequences

• Numerator of the expansion of e^(x + x^2 + x^3 + x^4).at n=9A090754
• E.g.f.: exp(x+x^2+x^3+x^4).at n=9A193930
• Triangle read by rows: T(n,k) is the number of nilpotent subpermutations on an n-set, each of nilpotency index less than or equal to k.at n=49A261764