A123533 Primes in A001855.

3, 5, 11, 17, 29, 37, 41, 59, 79, 89, 109, 349, 419, 433, 461, 503, 587, 601, 643, 727, 769, 809, 857, 881, 929, 937, 953, 977, 1009, 1033, 1049, 1097, 1129, 1153, 1193, 1201, 1217, 1249, 1289, 1297, 1321, 1361, 1409, 1433, 1481, 1489, 1553, 1601, 1609

Offset: 1

Author

Jonathan Vos Post, Nov 10 2006

Keywords

• easy
• nonn

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Intersection of A000040 and A001855.

Cf. A001768, A029837, A003071, A000337, A030190, A030308, A061168.

Programs

Maple

A001855 := proc(n) local c ; c := ceil(log[2](n)) ; n*c-2^c+1 ; end: for n from 1 to 300 do srts := A001855(n) : if isprime(srts) then printf("%d, ",srts) ; fi ; od : # R. J. Mathar, Dec 16 2006

Mathematica

Select[Accumulate[BitLength[Range[0, 300]]], PrimeQ] (* Paolo Xausa, Jun 28 2024 *)

Extensions

Corrected and extended by R. J. Mathar, Dec 16 2006