A113924 a(n) = gcd(A113605(n+1), A113605(n)). Also, for n >= 2, a(n) = A113605(n+2) - A113605(n-1).

1, 1, 1, 2, 1, 3, 1, 1, 4, 1, 1, 5, 1, 2, 1, 1, 1, 1, 8, 1, 3, 1, 1, 2, 1, 1, 1, 11, 2, 1, 1, 1, 1, 2, 1, 1, 5, 1, 4, 1, 1, 1, 1, 2, 19, 1, 1, 1, 10, 1, 7, 3, 1, 2, 1, 1, 1, 1, 6, 1, 1, 1, 5, 6, 1, 1, 1, 1, 2, 1, 3, 7, 1, 4, 1, 1, 1, 5, 2, 1, 1, 1, 1, 2, 1, 1

Offset: 1

Author

Leroy Quet, Jan 30 2006

Keywords

• nonn

Crossrefs

Cf. A113605.

Programs

Maple

A113605 := proc(n) option remember ; if n <=3 then 1 ; else A113605(n-3)+gcd(A113605(n-1),A113605(n-2)) ; fi ; end: A113924 := proc(n) gcd(A113605(n+1),A113605(n)) ; end; seq(A113924(n),n=1..80) ; # R. J. Mathar, Jan 31 2008

PARI

lista(nn) = my(w, x=1, y=1, z=1); print1("1"); for(n=2, nn, w=x+gcd(y, z); print1(", ", w-x); x=y; y=z; z=w); \\ Jinyuan Wang, Aug 10 2021

Extensions

More terms from R. J. Mathar, Jan 31 2008

More terms from Jinyuan Wang, Aug 10 2021