A071776 Related to Pisano periods: n such that the period of Fibonacci numbers mod n equals 3*(n+2).

6, 14, 26, 74, 86, 134, 146, 194, 206, 254, 314, 326, 386, 446, 554, 566, 626, 674, 734, 746, 794, 866, 914, 926, 974, 1046, 1094, 1154, 1214, 1226, 1286, 1346, 1454, 1466, 1514, 1574, 1646, 1706, 1754, 1766, 1814, 1874, 1994, 2066, 2126, 2186, 2234, 2246

Offset

1,1

Comments

a(n)/2 are primes with final digit 3 or 7 among primes in a related sequence: "m such that the period of Fibonacci numbers mod m equals 2*(m+1)".

Links

Table of n, a(n) for n=1..48.

Prog

(PARI) for(n=2, 4000, t=3*(n+2); good=1; if(fibonacci(t)%n==0, for(s=0, t, if(fibonacci(t+s)%n!=fibonacci(s)%n, good=0; break); if(s>1&&s<t-1&&fibonacci(s)%n==0, cur=s; good2=1; for(ss=0, s, if(fibonacci(ss+s)%n!=fibonacci(ss)%n, good2=0; break)); if(good2, good=0; break); ); ); if(good, print1(n, ", ")))) (Klasen)

Crossrefs

Cf. A071774, A001175.

Sequence in context: A168648 A093776 A107317 * A063590 A349723 A128806

Adjacent sequences: A071773 A071774 A071775 * A071777 A071778 A071779

Keyword

easy,nonn

Author

Benoit Cloitre, Jun 04 2002

Extensions

More terms from Lambert Klasen (Lambert.Klasen(AT)gmx.net), Dec 21 2004

Status

approved