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A195986
Exponent of the largest power of 2 that divides 5^n - 3^n.
2
1, 4, 1, 5, 1, 4, 1, 6, 1, 4, 1, 5, 1, 4, 1, 7, 1, 4, 1, 5, 1, 4, 1, 6, 1, 4, 1, 5, 1, 4, 1, 8, 1, 4, 1, 5, 1, 4, 1, 6, 1, 4, 1, 5, 1, 4, 1, 7, 1, 4, 1, 5, 1, 4, 1, 6, 1, 4, 1, 5, 1, 4, 1, 9, 1, 4, 1, 5, 1, 4, 1, 6, 1, 4, 1, 5, 1, 4, 1, 7, 1, 4, 1, 5, 1, 4
OFFSET
1,2
COMMENTS
Conjecture: a(n) = 1 if A090740 = 1, else a(n) = A090740(n)+1.
LINKS
FORMULA
a(n) = A007814(A005058(n)). - Antti Karttunen, Nov 06 2018
MATHEMATICA
Table[IntegerExponent[5^n - 3^n, 2], {n, 100}] (* T. D. Noe, Oct 12 2011 *)
PROG
(PARI) A195986(n) = valuation(5^n - 3^n, 2); \\ Antti Karttunen, Nov 06 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
John W. Layman, Oct 12 2011
EXTENSIONS
Name clarified by Antti Karttunen, Nov 06 2018
STATUS
approved