A263578 Positive values of k such that A014286(k) is divisible by k.

1, 3, 18, 24, 42, 48, 72, 96, 120, 138, 144, 192, 216, 240, 258, 264, 282, 288, 336, 360, 384, 402, 432, 480, 498, 576, 600, 618, 642, 648, 672, 714, 720, 744, 762, 768, 864, 912, 960, 978, 1002, 1008, 1080, 1104, 1152, 1200, 1224, 1296, 1320, 1338, 1344, 1362

Offset: 1

Author

Altug Alkan, Oct 22 2015

Keywords

• nonn
• easy

Comments

Sequence is interesting because of the values of a(n) - a(n-1). For a(n) < 10000, the most common repeated values of a(n) - a(n-1) are 24 and 6. Will this situation continue?

Examples

			a(2) = 3 because Fibonacci(1) + 2 * Fibonacci(2) + 3 * Fibonacci(3) = 9, which is divisible by 3.
		

Crossrefs

Cf. A000045, A014286.

Programs

Mathematica

Select[Range@ 1584, Divisible[Sum[i Fibonacci@ i, {i, 0, #}], #] &] (* Michael De Vlieger, Oct 22 2015 *)

PARI

for(n=1, 2000, if(sum(k=1, n, k*fibonacci(k)) % n == 0, print1(n, ", ")))