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A121874
Numbers n such that Fibonacci(n) == 0 (mod triangular(n)).
2
1, 10, 60, 108, 180, 240, 250, 540, 600, 660, 768, 1008, 1200, 1320, 1620, 1800, 1860, 2160, 2520, 2688, 2736, 3000, 3060, 3300, 3360, 3528, 3888, 4200, 4800, 4860, 4968, 5050, 5280, 5520, 5580, 5880, 6120, 6480, 6600, 6720, 6840, 7320, 7560, 7680, 8100
OFFSET
1,2
COMMENTS
Zero terms of A121343.
LINKS
FORMULA
Numbers n where A000045(n) == 0 (mod A000217(n)).
MATHEMATICA
Select[Range@10000, Mod[Fibonacci@#, #(# + 1)/2] == 0 &]
PROG
(PARI) for(n=1, 8250, if(Mod(fibonacci(n), binomial(n+1, 2))==0, print1(n", "))) \\ G. C. Greubel, Oct 08 2019
(Magma) [n: n in [1..8250] | Fibonacci(n) mod Binomial(n+1, 2) eq 0]; // G. C. Greubel, Oct 08 2019
(Sage) [n for n in (1..8500) if Mod(fibonacci(n), binomial(n+1, 2))==0] # G. C. Greubel, Oct 08 2019
(GAP) Filtered([1..8250], n-> (Fibonacci(n) mod Binomial(n+1, 2))=0 ); # G. C. Greubel, Oct 08 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Aug 31 2006
STATUS
approved