A138537 Primes p_n for which A140141(n) = 2p_n, where p_n = n-th prime (A000040).

11, 23, 29, 31, 47, 53, 59, 67, 71, 79, 83, 103, 107, 127, 131, 137, 139, 149, 151, 167, 173, 179, 191, 197, 199, 211, 223, 227, 229, 239, 251, 263, 269, 271, 283, 293, 307, 311, 317, 331, 347, 359, 367, 373, 379, 383, 389, 419, 431, 439, 443, 463, 467, 479

Offset

1,1

Comments

Perhaps the same as A058340, but need proof. - Ray Chandler, May 20 2008

The first member of this sequence not in A058340 is 295937. - Robert Israel, Aug 12 2016

Links

Robert Israel, Table of n, a(n) for n = 1..20000

Maple

filter:= n -> isprime(n) and numtheory:-invphi(numtheory:-phi(n))[2] = 2*n:
select(filter, [seq(i, i=2..1000)]); # Robert Israel, Aug 12 2016

Crossrefs

Cf. A000010, A000040, A039649, A058340, A140141.

Sequence in context: A232085 A086102 A058340 * A271983 A136000 A054723

Adjacent sequences: A138534 A138535 A138536 * A138538 A138539 A138540

Keyword

nonn

Author

Vladimir Shevelev, May 10 2008

Extensions

Corrected and extended by Ray Chandler, May 20 2008

Status

approved