A080668 Numbers of the form n!+n^3.

2, 10, 33, 88, 245, 936, 5383, 40832, 363609, 3629800, 39918131, 479003328, 6227022997, 87178293944, 1307674371375, 20922789892096, 355687428100913, 6402373705733832, 121645100408838859, 2432902008176648000

Offset: 1

Author

Cino Hilliard, Mar 02 2003

Keywords

• easy
• nonn

Comments

Sum of the reciprocals = 0.6470299890164780452999873886..

Programs

Mathematica

Table[n!+n^3,{n,20}] (* Harvey P. Dale, May 21 2015 *)

PARI

factncub(n) = {sr=0; for(x=1,n, y=x!+x^3; print1(y","); sr+=1.0/y; ); print(); print(sr) }