A331976 Odd integers m that divide the sum of the first m nonzero Fibonacci numbers.

1, 77, 319, 323, 1517, 3021, 4757, 6479, 7221, 8159, 8229, 9797, 11663, 12597, 13629, 13869, 14429, 14949, 16637, 18407, 19043, 19437, 23407, 24947, 25437, 30049, 30621, 34943, 34989, 35207, 39203, 43677, 44099, 47519, 51983, 53663, 55221, 65471, 70221, 77837, 78089, 79547

Offset: 1

Author

Michel Marcus, Feb 03 2020

Keywords

• nonn

Comments

Not all terms are squarefree, for instance 13869, 14949, 43677, 93357, ... are not.

A subsequence of A124456, missing just the even terms A124456({2, 155, 397, 469, ...}) = {2, 758624, 7057466, 10805846, ...}. - M. F. Hasler, Feb 06 2020

There are infinitely many terms. - Oisín Flynn-Connolly, May 01 2025

Links

• Giovanni Resta, Table of n, a(n) for n = 1..10000
• Oisín Flynn-Connolly, On the divisibility of sums of Fibonacci numbers, arXiv:2504.09938 [math.NT], 2025.
• Daniel Yaqubi and Amirali Fatehizadeh, Some results on average of Fibonacci and Lucas sequences, arXiv:2001.11839 [math.CO], 2020.

Crossrefs

Odd terms in A111035, A124456.

Programs

PARI

forstep(n=1,oo,2, is_A111035(n) && print1(n",")) \\ M. F. Hasler, Feb 06 2020

Formula

Equals A124456 without even terms. - M. F. Hasler, Feb 06 2020