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A121171 Largest prime divisor of Lucas[5n], where Lucas[k] = A000032[k]. 4
11, 41, 31, 2161, 151, 2521, 911, 3041, 541, 570601, 39161, 20641, 24571, 12317523121, 18451, 23725145626561, 12760031, 10783342081, 87382901, 5738108801, 767131, 59996854928656801, 686551, 23735900452321, 28143378001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Final digit of a(n) is 1. Mod[a(n),10] = 1. Final digit of many prime divisors of Lucas[5n] is 1.

LINKS

Table of n, a(n) for n=1..25.

MATHEMATICA

Table[Max[Flatten[FactorInteger[Fibonacci[5n-1]+Fibonacci[5n+1]]]], {n, 1, 40}]

CROSSREFS

Cf. A000032, A000045.

Sequence in context: A065144 A089348 A088622 * A239790 A065079 A065049

Adjacent sequences:  A121168 A121169 A121170 * A121172 A121173 A121174

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Aug 14 2006

STATUS

approved

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Last modified September 18 09:56 EDT 2019. Contains 327169 sequences. (Running on oeis4.)