A104088 Largest prime <= 3^n.

3, 7, 23, 79, 241, 727, 2179, 6553, 19681, 59029, 177131, 531383, 1594301, 4782961, 14348891, 43046623, 129140153, 387420479, 1162261453, 3486784393, 10460353199, 31381059607, 94143178807, 282429536453, 847288609423

Offset

1,1

Links

Table of n, a(n) for n=1..25.

Mathematica

PrimePrev[n_]:=Module[{k=n}, While[ !PrimeQ[k], k-- ]; k]; f[n_]:=3^n; lst={}; Do[AppendTo[lst, PrimePrev[f[n]]], {n, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Feb 26 2010 *)
Join[{3}, NextPrime[3^Range[2, 50], -1]] (* Harvey P. Dale, Jun 20 2021 *)

Prog

(PARI) g(n, b) = for(x=0, n, print1(precprime(b^x)", "))

Crossrefs

Sequence in context: A341071 A148712 A208591 * A169650 A346771 A136508

Adjacent sequences: A104085 A104086 A104087 * A104089 A104090 A104091

Keyword

easy,nonn

Author

Cino Hilliard, Mar 03 2005

Status

approved