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A217738 Numbers k such that Fibonacci(k) is divisible by k*(k+1). 10
60, 108, 180, 240, 540, 600, 660, 768, 1008, 1200, 1320, 1620, 1800, 1860, 2160, 2520, 2688, 2736, 3000, 3060, 3300, 3360, 3528, 3888, 4200, 4800, 4860, 4968, 5280, 5520, 5580, 5880, 6120, 6480, 6600, 6720, 6840, 7320, 7560, 7680, 8100, 8208, 8640, 9000, 9180, 9240, 9600 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Indices of 0's in A217737.

Conjectures: the sequence is infinite; all terms are divisible by 12.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..1000 (first 370 terms from Harvey P. Dale)

MATHEMATICA

Select[Range[10000], Divisible[Fibonacci[#], #(#+1)]&] (* Harvey P. Dale, Aug 14 2014 *)

PROG

(Python)

prpr, prev = 0, 1

for i in range(1, 1000):

    cur = prpr + prev

    a = prev % (i*(i+1))

    if a==0:

      print(str(i), end=', ')

    prpr, prev = prev, cur

CROSSREFS

Cf. A000045, A002378, A217737.

Sequence in context: A044001 A258700 A008887 * A182683 A174601 A306908

Adjacent sequences:  A217735 A217736 A217737 * A217739 A217740 A217741

KEYWORD

nonn

AUTHOR

Alex Ratushnyak, Mar 22 2013

STATUS

approved

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Last modified December 5 06:52 EST 2021. Contains 349543 sequences. (Running on oeis4.)