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A094105
Primes of the form prime(n) + 2*prime(n+1).
5
13, 19, 29, 37, 47, 127, 137, 181, 283, 307, 317, 367, 389, 541, 563, 577, 587, 677, 743, 811, 839, 907, 929, 937, 947, 1031, 1093, 1283, 1297, 1453, 1489, 1567, 1801, 1847, 1913, 2027, 2347, 2381, 2467, 2477, 2617, 2647, 2657, 2729, 2749, 2777, 2803, 2819
OFFSET
1,1
COMMENTS
No intersection with A094104 (Primes of the form 2*prime(m)+prime(m+1)): an integer of the form 2*prime(m)+prime(m+1) cannot be of the form prime(n)+2*prime(n+1). - Zak Seidov, Feb 16 2012
EXAMPLE
a(9) = 89 + 2*97 = 283.
MATHEMATICA
f[n_] := (Prime[n] + 2Prime[n + 1]); f[ # ] & /@ Select[Range[160], PrimeQ[f[ # ]] &] (* Robert G. Wilson v, May 07 2004 *)
Select[#[[1]]+2*#[[2]]&/@Partition[Prime[Range[200]], 2, 1], PrimeQ] (* Harvey P. Dale, May 08 2015 *)
Select[Table[Prime[n] + 2 Prime[n + 1], {n, 200}], PrimeQ] (* Vincenzo Librandi, Jul 25 2015 *)
PROG
(PARI) q=2; forprime(p=3, 1000, if(isprime(r=q+2*p), print1(r, ", ")); q=p)
(Magma) [a: n in [1..200] | IsPrime(a) where a is NthPrime(n) + 2*NthPrime(n+1)]; // Vincenzo Librandi, Jul 25 2015
CROSSREFS
Cf. A094104.
Sequence in context: A063640 A092104 A281483 * A073620 A089391 A038954
KEYWORD
nonn,easy
AUTHOR
Giovanni Teofilatto, May 02 2004
EXTENSIONS
Corrected and extended by Klaus Brockhaus and Robert G. Wilson v, May 07 2004
STATUS
approved