A229554 a(n) = 7*n! + 1.

8, 8, 15, 43, 169, 841, 5041, 35281, 282241, 2540161, 25401601, 279417601, 3353011201, 43589145601, 610248038401, 9153720576001, 146459529216001, 2489811996672001, 44816615940096001, 851515702861824001, 17030314057236480001, 357636595201966080001

Offset: 0

Author

Vincenzo Librandi, Sep 30 2013

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..200

Crossrefs

Cf. sequences of the type k*n!+1: A038507 (k=1), A052898 (k=2), A173324 (k=3), A173322 (k=4), A173319 (k=5), A173314 (k=6), this sequence (k=7).

Programs

Magma

[7*Factorial(n)+1: n in [0..25]];

Magma

[8] cat [n eq 1 select n+7 else n*Self(n-1)-n+1: n in [1..25]];

Mathematica

Table[7 n! + 1, {n, 0, 25}]

Formula

a(0)=8, a(n) = n*a(n-1)-n+1.

E.g.f.: 7/(1-x)+exp(x). - Geoffrey Critzer, Sep 30 2013