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A111257
Primes in A111256.
0
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
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
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Nov 01 2005
STATUS
approved