A121874 Numbers n such that Fibonacci(n) == 0 (mod triangular(n)).

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

Giovanni Resta, Table of n, a(n) for n = 1..1000

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

Cf. A121343, A000045, A000217.

Sequence in context: A046762 A066290 A065641 * A144560 A076160 A266732

Adjacent sequences: A121871 A121872 A121873 * A121875 A121876 A121877

Keyword

nonn

Author

Robert G. Wilson v, Aug 31 2006

Status

approved