0,2

A064680(A064680(a(n))) = a(n) - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Oct 19 2001

a(n)=4+a(n-3).

G.f.: (1+x+x^2+x^3)/((1-x)*(1-x^3)) - Michael Somos Jan 12 2000.

Nearest integer to sum(k>n, 1/k^4)/sum(k>n, 1/k^5) - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 12 2003

(PARI) a(n)=1+n+n\3

Cf. A001651.

Sequence in context: A109237 A059531 A039053 this_sequence A059557 A048103 A092418

Adjacent sequences: A042965 A042966 A042967 this_sequence A042969 A042970 A042971

nonn

njas