A280728 Number of even divisors of Lucas(n).

1, 0, 0, 2, 0, 0, 3, 0, 0, 4, 0, 0, 4, 0, 0, 8, 0, 0, 8, 0, 0, 8, 0, 0, 4, 0, 0, 8, 0, 0, 12, 0, 0, 8, 0, 0, 8, 0, 0, 16, 0, 0, 24, 0, 0, 64, 0, 0, 8, 0, 0, 16, 0, 0, 20, 0, 0, 16, 0, 0, 32, 0, 0, 64, 0, 0, 24, 0, 0, 32, 0, 0, 8, 0, 0, 128, 0, 0, 12, 0, 0

Offset: 0

Author

Vincenzo Librandi, Jan 09 2017

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A000032, A183063, A193495.

Programs

Mathematica

a[n_]:=Block[{d=Divisors[LucasL[n]]}, Count[EvenQ[d], True]]; Table[a[n], {n, 0, 80}]

Formula

a(n) = A183063(A000032(n)).

Extensions

Offset corrected by Amiram Eldar, Sep 03 2019