OFFSET
1,2
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?
EXAMPLE
a(2) = 3 because Fibonacci(1) + 2 * Fibonacci(2) + 3 * Fibonacci(3) = 9, which is divisible by 3.
MATHEMATICA
Select[Range@ 1584, Divisible[Sum[i Fibonacci@ i, {i, 0, #}], #] &] (* Michael De Vlieger, Oct 22 2015 *)
PROG
(PARI) for(n=1, 2000, if(sum(k=1, n, k*fibonacci(k)) % n == 0, print1(n, ", ")))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Altug Alkan, Oct 22 2015
STATUS
approved