A013607 a(n) = 6^n-prevprime(6^n).

1, 5, 5, 5, 17, 7, 17, 7, 7, 7, 59, 19, 17, 13, 7, 19, 49, 13, 19, 7, 23, 35, 19, 89, 17, 119, 29, 55, 5, 19, 5, 59, 85, 5, 17, 35, 59, 83, 49, 115, 19, 23, 43, 109, 103, 7, 23, 19, 7, 245, 43, 13, 5, 55, 89, 83, 143, 53, 53, 383, 7, 55, 113, 37, 5, 23, 143, 115

Offset

1,2

Links

Daniel Starodubtsev, Table of n, a(n) for n = 1..1000

Formula

a(n) = A000400(n) - A104091(n). - Michel Marcus, Jan 13 2020

Maple

seq(6^i-prevprime(6^i), i=1..100);

Mathematica

pp[n_]:=Module[{n6=6^n}, n6-NextPrime[n6, -1]]; Array[pp, 70] (* Harvey P. Dale, May 04 2011 *)
#-NextPrime[#, -1]&/@(6^Range[70]) (* Harvey P. Dale, May 28 2023 *)

Crossrefs

Cf. A000400 (6^n), A104091 (largest prime <= 6^n).

Sequence in context: A334934 A131286 A183390 * A260960 A283711 A365368

Adjacent sequences: A013604 A013605 A013606 * A013608 A013609 A013610

Keyword

nonn

Author

James Kilfiger (mapdn(AT)csv.warwick.ac.uk)

Status

approved