A069197 a(1)=1 a(2)=4 a(n+2)=(a(n+1)+a(n))/3 if (a(n+1)+a(n)==0 (mod 3)); a(n+2)=(a(n+1)+a(n))/2 if (a(n+1)+a(n)==0 (mod 2)); a(n+2)=a(n+1)+a(n) otherwise.

1, 4, 5, 3, 4, 7, 11, 6, 17, 23, 20, 43, 21, 32, 53, 85, 46, 131, 59, 95, 77, 86, 163, 83, 82, 55, 137, 64, 67, 131, 66, 197, 263, 230, 493, 241, 367, 304, 671, 325, 332, 219, 551, 385, 312, 697, 1009, 853, 931, 892, 1823, 905, 1364, 2269, 1211, 1160, 2371, 1177

Offset

1,2

Comments

A Collatz-Fibonacci mixture. Does this sequence diverge to infinity? Conjecture : if a(1)=1 and a(2)=2 sequence is constant = 1, if a(2)=5 sequence is cyclic = (5,2,7,3) but if a(2)=m, different from 2 or 5, sequence diverges.

Links

Table of n, a(n) for n=1..58.

Crossrefs

Sequence in context: A008962 A175725 A212711 * A021692 A222627 A107793

Adjacent sequences: A069194 A069195 A069196 * A069198 A069199 A069200

Keyword

easy,nonn

Author

Benoit Cloitre, Apr 11 2002

Status

approved