A200049 - OEIS

%I #16 Oct 30 2018 10:31:02

%S 2,3,5,7,9,12,14,16,20,21,27,29,30,34,37,44,45,48,52,53,58,61,65,71,

%T 75,76,78,79,84,93,97,100,101,109,111,115,119,122,128,132,133,142,144,

%U 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

%N Positions of squares of odd primes among odd powerful numbers A062739.

%H Zak Seidov, <a href="/A200049/b200049.txt">Table of n, a(n) for n = 1..1000</a>

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

%o (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

%Y Cf. A000040, A062739.

%K nonn

%O 1,1

%A _Zak Seidov_, Nov 13 2011