A072713 a(1)=a(2)=a(3)=a(4)=a(5)=1; for n>5, a(n)*a(n-5) = a(n-1)*a(n-2)*a(n-3)*a(n-4)+1.

1, 1, 1, 1, 1, 2, 3, 7, 43, 1807, 815861, 147917502976, 1339566593057489572791, 6793440021984612817314824762112917427331, 607759339422199886496126580428414916308278553796099069562650354036190535151

Offset

1,6

Links

Seiichi Manyama, Table of n, a(n) for n = 1..19

Mathematica

nxt[{a_, b_, c_, d_, e_}]:={b, c, d, e, (b*c*d*e+1)/a}; Join[{1, 1, 1, 1}, Transpose[ NestList[nxt, {1, 1, 1, 1, 1}, 15]][[5]]] (* Harvey P. Dale, Oct 03 2012 *)

Crossrefs

Cf. A005246, A051786.

Sequence in context: A051786 A133400 A113845 * A000058 A129871 A075442

Adjacent sequences: A072710 A072711 A072712 * A072714 A072715 A072716

Keyword

nonn

Author

Benoit Cloitre, Aug 07 2002

Status

approved