A200049 Positions of squares of odd primes among odd powerful numbers A062739.

2, 3, 5, 7, 9, 12, 14, 16, 20, 21, 27, 29, 30, 34, 37, 44, 45, 48, 52, 53, 58, 61, 65, 71, 75, 76, 78, 79, 84, 93, 97, 100, 101, 109, 111, 115, 119, 122, 128, 132, 133, 142, 144, 146, 147, 157, 165, 169, 170, 172, 178, 180, 188, 193, 198, 202, 203, 207, 211, 213, 221, 231, 233, 234, 238, 251, 254, 261, 263, 267, 271

Offset: 1

Author

Zak Seidov, Nov 13 2011

Keywords

• nonn

Links

• Zak Seidov, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A000040, A062739.

Programs

PARI

lista(nn) = select(x->(issquare(x) && isprime(sqrtint(x))), select(x->(ispowerful(x) && (x % 2)), vector(nn, k, k)), 1); \\ Michel Marcus, Jun 18 2017

Formula

A062739(a(n)) = (A000040(n+1))^2.