A112882 Indices of prime Padovan numbers: values of k such that A000931(k+5) is prime.

3, 4, 5, 7, 8, 14, 19, 30, 37, 84, 128, 469, 666, 1262, 1573, 2003, 2210, 2289, 4163, 5553, 6567, 8561, 11230, 18737, 35834, 44259, 536485, 727734

Offset

1,1

Links

Table of n, a(n) for n=1..28.

Eric Weisstein's World of Mathematics, Integer Sequence Primes.

Eric Weisstein's World of Mathematics, Padovan Prime.

Formula

a(n) = A152870(n) - 5. - Amiram Eldar, Nov 10 2024

Mathematica

Position[RootSum[-1 - # + #^3 &, (5 - 6 # + 4 #^2) #^Range[2000] &]/23, _?PrimeQ] - 5 // Flatten (* Eric W. Weisstein, Jun 05 2026 *)

Crossrefs

Cf. A000931, A100891, A152870.

Sequence in context: A154571 A174269 A388054 * A180152 A385564 A162610

Adjacent sequences: A112879 A112880 A112881 * A112883 A112884 A112885

Keyword

nonn,more

Author

Eric W. Weisstein, Oct 05 2005

Extensions

a(27) from Eric W. Weisstein, May 22 2009

a(28) from Eric W. Weisstein, Apr 10 2011

Status

approved