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%I #16 Feb 15 2019 03:05:53
%S 1,2,7,23,53,97,151,227,311,419,541,661,827,1009,1193,1427,1619,1879,
%T 2143,2437,2741,3083,3461,3803,4211,4637,5051,5519,6007,6481,6997,
%U 7573,8161,8737,9341,9931,10627,11321,12049,12743,13499,14327,15101,15877,16747,17609
%N One and prime numbers whose prime index is a perfect square.
%F a(n) = A011757(n-1) for n > 1. - _Alois P. Heinz_, Jan 17 2019
%t Array[Prime[#^2]&,20]
%o (PARI) vector(50, n, if (n==1, 1, prime((n-1)^2))) \\ _Michel Marcus_, Feb 15 2019
%Y Cf. A000290, A000720, A001248, A011757, A026478, A056239, A323520, A323521, A323525, A323527, A323528.
%K nonn
%O 1,2
%A _Gus Wiseman_, Jan 17 2019