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A112786
Starting from P0=3, the sequence list the minimum prime P1>P0 for which the expression P=P1+P0+1 is also a prime. The search then restarts from P1.
2
3, 7, 11, 17, 19, 23, 29, 31, 41, 47, 53, 59, 67, 71, 79, 83, 89, 101, 109, 113, 127, 149, 157, 173, 179, 193, 227, 229, 233, 257, 263, 277, 293, 307, 311, 331, 359, 367, 383, 389, 397, 431, 449, 457, 461, 467, 479, 487, 503, 509, 521, 541, 587, 593, 599, 601
OFFSET
0,1
LINKS
EXAMPLE
3+5+1=9 is not a prime.
3+7+1=11 is a prime: 7 is in the sequence.
7+11+1=19 is a prime: 11 is in the sequence.
11+13+1=25 is not a prime.
11+17+1=29 is a prime: 17 is in the sequence.
MAPLE
P:=proc(n) local i, w; w:=3; for i from 3 by 1 to n do if isprime(w+ithprime(i)+1) then print(ithprime(i)); w:=ithprime(i); fi; od; end: P(500);
MATHEMATICA
f[n_]:=Module[{p=NextPrime[n]}, While[!PrimeQ[n+p+1], p=NextPrime[p]]; p]; Join[{p=3}, Table[p=f[p], {n, 60}]] (* Vladimir Joseph Stephan Orlovsky, Feb 07 2012 *)
nxt[p_]:=Module[{np=NextPrime[p]}, While[!PrimeQ[p+np+1], np=NextPrime[np]]; np]; NestList[nxt, 3, 60] (* Harvey P. Dale, Jun 05 2023 *)
CROSSREFS
Sequence in context: A118000 A121640 A319258 * A023211 A038981 A065376
KEYWORD
easy,nonn
AUTHOR
Amarnath Murthy, Jan 02 2006
EXTENSIONS
More terms from Paolo P. Lava and Giorgio Balzarotti, Mar 07 2007
Edited by N. J. A. Sloane at the suggestion of Stefan Steinerberger, Jun 07 2007
STATUS
approved