A071697 Product of twin primes of form (4*k+1,4*k+3), k>0.

35, 323, 899, 1763, 10403, 19043, 22499, 39203, 72899, 79523, 213443, 272483, 324899, 381923, 412163, 656099, 675683, 736163, 777923, 1102499, 1127843, 1512899, 1633283, 1664099, 1695203, 2196323, 2883203, 2965283, 3526883, 3802499, 3992003, 4334723, 4536899

Offset: 1

Author

Reinhard Zumkeller, Jun 04 2002

Keywords

• nonn

Crossrefs

Cf. A037074, A071700.

Cf. A071695, A071696.

Programs

Magma

[16*n^2+16*n+3: n in [1..700]| IsPrime(4*n+1) and IsPrime(4*n+3)]; // Vincenzo Librandi, Feb 24 2015

PARI

lista(nn) = {forprime(p=3, nn, if ((((p-1) % 4) == 0) && isprime(p+2), print1(p*(p+2), ", ")););} \\ Michel Marcus, Feb 24 2015

Formula

a(n) = A071695(n)*A071696(n).

Extensions

More terms from Michel Marcus, Feb 24 2015