A111257 Primes in A111256.

11, 17, 19, 29, 31, 41, 43, 53, 67, 73, 79, 89, 97, 107, 113, 127, 139, 151, 157, 163, 181, 191, 199, 211, 223, 241, 271, 277, 307, 337, 347, 353, 373, 389, 409, 439, 461, 463, 491, 499, 509, 521, 547, 577, 601, 619, 631, 701, 709, 733, 757, 769, 773, 787, 821

Offset

1,1

Links

Table of n, a(n) for n=1..55.

Formula

b(n) = If Prime[n+2]+Prime[n]+1 is prime then Prime[n+2]+Prime[n]+1 else Prime[n+1]+Prime[n]+1 a(n)=If b(n) if prime then b(n)

Mathematica

b=Table[If[PrimeQ[Prime[n + 2] + Prime[n] + 1], Prime[n + 2] + Prime[n] + 1, Prime[n + 1] + Prime[n] + 1], {n, 1, 200}] a=Flatten[Table[If[PrimeQ[b[[n]]], b[[n]], {}], {n, 1, 200}]]

Crossrefs

Sequence in context: A019412 A178641 A226682 * A032677 A225677 A344477

Adjacent sequences: A111254 A111255 A111256 * A111258 A111259 A111260

Keyword

nonn

Author

Roger L. Bagula, Nov 01 2005

Status

approved