Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #5 Oct 01 2013 17:58:02
%S 2,2,3,3,5,6,7,8,5,10,11,12,13,14,15,7,17,18,19,20,21,22,23,24,11,26,
%T 27,28,29,30,31,32,33,34,35,13,37,38,39,40,41,42,43,44,45,46,47,48,17,
%U 50,51,52,53,54,55,56,57,58,59,60,61,62,63,19,65,66,67,68,69,70,71,72,73
%N If n is square, replace with the sqrt(n)-th prime.
%e sqrt(16) = 4. replace 16 with prime(4) = 7.
%t snp[n_]:=Module[{s=Sqrt[n]},If[IntegerQ[s],Prime[s],n]]; Array[snp,80] (* _Harvey P. Dale_, Jun 21 2013 *)
%o (PARI) replsqpx(n) = { for(x=1,n, if(issquare(x),y=prime(floor(sqrt(x))),y=x); print1(floor(y)",")) }
%K nonn
%O 1,1
%A _Cino Hilliard_, Aug 23 2004