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A106296
Period of the Lucas 4-step sequence A073817 mod prime(n).
3
5, 26, 312, 342, 120, 84, 4912, 6858, 12166, 280, 61568, 1368, 240, 162800, 103822, 303480, 205378, 226980, 100254, 357910, 2664, 998720, 1157520, 9320, 368872, 1030300, 10608, 1225042, 2614040, 13874, 2048382, 4530768, 136, 772880, 3307948
OFFSET
1,1
COMMENTS
This sequence is the same as the period of Fibonacci 4-step sequence (A000078) mod prime(n) except for n=103, which corresponds to the prime 563 because the discriminant of the characteristic polynomial x^4-x^3-x^2-x-1 is -563. We have a(n) < prime(n) for primes 563 and A106280.
LINKS
Eric Weisstein's World of Mathematics, Fibonacci n-Step Number
FORMULA
a(n) = A106295(prime(n)).
MATHEMATICA
n=4; Table[p=Prime[i]; a=Join[Table[ -1, {n-1}], {n}]; a=Mod[a, p]; a0=a; k=0; While[k++; s=Mod[Plus@@a, p]; a=RotateLeft[a]; a[[n]]=s; a!=a0]; k, {i, 60}]
CROSSREFS
Cf. A106273 (discriminant of the polynomial x^n-x^(n-1)-...-x-1), A106280 (primes p such that x^4-x^3-x^2-x-1 mod p has 4 distinct zeros), A106295.
Sequence in context: A203198 A197784 A279738 * A295114 A060516 A077537
KEYWORD
nonn
AUTHOR
T. D. Noe, May 02 2005
STATUS
approved