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A078654
a(n) = prime(k) where k = n-th prime congruent to 3 mod 4.
2
5, 17, 31, 67, 83, 127, 191, 211, 277, 331, 353, 401, 431, 563, 587, 709, 739, 797, 877, 967, 991, 1063, 1153, 1217, 1297, 1409, 1433, 1499, 1597, 1669, 1741, 1847, 2027, 2063, 2221, 2341, 2417, 2477, 2609, 2647, 2897, 3001, 3067, 3109, 3299, 3319, 3407
OFFSET
1,1
LINKS
FORMULA
a(n) = A000040(A002145(n)). [Bruno Berselli, Aug 14 2012]
MATHEMATICA
With[{pc14=Select[Prime[Range[1000]], Mod[#, 4]==3&]}, Flatten[Table[Prime[Take[pc14, {n}]], {n, 100}]]] (* Vincenzo Librandi, Aug 13 2012 *)
PROG
(PARI) tpip(n, m, r) = {sr=0; forprime(x=3, n, if(x%m == r, v=prime(x); sr+=1.0/v; print1(v" "); ) ); print(); print("m="m" r="r" sr="sr); }
(Magma) [NthPrime(n): n in PrimesUpTo(500) | n mod 4 eq 3]; // Bruno Berselli, Aug 14 2012
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Dec 14 2002
EXTENSIONS
Offset changed from 0 to 1 by Vincenzo Librandi, Aug 14 2012
STATUS
approved