A067826 Primes p such that sigma(2*p+1) > 3*(p+1).

31, 37, 67, 73, 97, 127, 157, 199, 229, 241, 277, 283, 307, 313, 331, 337, 367, 379, 397, 409, 457, 487, 499, 547, 577, 607, 619, 643, 661, 727, 757, 769, 787, 823, 829, 877, 907, 937, 967, 997, 1039, 1087, 1117, 1123, 1237, 1249, 1291, 1297, 1327, 1447

Offset

1,1

Comments

Equivalently sequence gives primes in A053224(k)/2 when A053224(k) is even.

Links

Table of n, a(n) for n=1..50.

Prog

(PARI) isok(p) = isprime(p) && (sigma(2*p+1) > 3*(p+1)); \\ Michel Marcus, Nov 23 2013

Crossrefs

Cf. A053224.

Sequence in context: A156974 A215431 A082957 * A107013 A107012 A276305

Adjacent sequences: A067823 A067824 A067825 * A067827 A067828 A067829

Keyword

nonn

Author

Benoit Cloitre, Feb 08 2002

Status

approved