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A030671 Smallest extension of n-th prime which is a square.

%I A030671 #11 Sep 06 2016 03:13:59
%S A030671 25,36,529,729,1156,1369,1764,196,2304,2916,3136,3721,41209,4356,4761,
%T A030671 5329,5929,61009,676,71289,7396,7921,83521,89401,97344,101124,103041,
%U A030671 107584,109561,113569,12769,131044,137641,13924,149769,15129
%N A030671 Smallest extension of n-th prime which is a square.
%H A030671 Robert Israel, <a href="/A030671/b030671.txt">Table of n, a(n) for n = 1..10000</a>
%F A030671 a(n) = A030666(A000040(n)). - _Robert Israel_, Sep 05 2016
%e A030671 For n=2, the second prime is 3, and 36 is the smallest square that begins with 3, so a(2) = 36. - _Michael B. Porter_, Sep 06 2016
%p A030671 A030666:= proc(x) local d;
%p A030671 for d from 1 do
%p A030671   if ceil(sqrt(10^d*x)) <=  floor(sqrt(10^d*(x+1)-1)) then
%p A030671      return ceil(sqrt(10^d*x))^2
%p A030671 fi
%p A030671 od
%p A030671 end proc:
%p A030671 seq(A030666(ithprime(i)),i=1..100); # _Robert Israel_, Sep 05 2016
%Y A030671 Cf. A000040, A030666, A030672.
%K A030671 nonn,base
%O A030671 1,1
%A A030671 _Patrick De Geest_
%E A030671 Name edited by _Robert Israel_, Sep 06 2016