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A193294 Sum of even divisors of Fibonacci(n). 2
0, 0, 2, 0, 0, 14, 0, 0, 36, 0, 0, 390, 0, 0, 744, 0, 0, 5040, 0, 0, 11816, 0, 0, 154752, 0, 0, 213840, 0, 0, 1999872, 0, 0, 3564360, 0, 0, 46656000, 0, 0, 63517896, 0, 0, 526048320, 0, 0, 1465647264, 0, 0, 16665772032, 0, 0, 20377766312, 0, 0, 173039328000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..1000

EXAMPLE

a(6) = 14 because Fibonacci(6) = 8, and the sum of the even divisors {2, 4, 8} = 14.

MATHEMATICA

Table[Total[Select[Divisors[Fibonacci[n]], EvenQ[ # ]&]], {n, 75}]

PROG

(PARI) a(n)=if(n%3, 0, 2*sigma(fibonacci(n)/2)) \\ Charles R Greathouse IV, Jul 31 2011

CROSSREFS

Cf. A000045, A193291.

Sequence in context: A244139 A231031 A061848 * A231049 A231080 A231246

Adjacent sequences:  A193291 A193292 A193293 * A193295 A193296 A193297

KEYWORD

nonn

AUTHOR

Michel Lagneau, Jul 21 2011

STATUS

approved

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Last modified November 14 07:19 EST 2019. Contains 329111 sequences. (Running on oeis4.)