%I #12 Jun 10 2018 11:31:57
%S 1,4,9,196,225,3136,4489,6084,841,10000,10201,10404,10609,12996,27225,
%T 27556,27889,39204,39601,40000,40401,40804,54289,54756,616225,617796,
%U 71289,71824,89401,90000,90601,10036224,1108809,10150596,1525225,1920996
%N Smallest square obtained by inserting one or more digits between every pair of consecutive digits of n^2.
%C If n^2 has k digits, there are (k-1) places where digit insertion takes place, and a(n) contains at least 2k-1 digits.
%o (PARI) { a(n) = m=Vec(Str(n^2)); r=0; k=#m-1; while(!r, forvec(w=vector(#m-2,i,[1,k-1]), v=vector(#w+1,i,if(i<=#w,w[i],k)-if(i>1,w[i-1])); forvec(u=vector(#v,i,[0,10^v[i]-1]), t=m[1]; for(i=1,#v, if(#Str(u[i])<v[i], t=concat(t,concat(vector(v[i]-#Str(u[i]),j,"0"))); ); t=concat([t,Str(u[i]),m[i+1]]); ); t=eval(t); if( issquare(t) && (r==0 || t<r), r=t); ); ,2); k++;); r } \\ _Max Alekseyev_, Feb 11 2012
%Y Cf. A080436, A080437.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Feb 21 2003
%E More terms from _Max Alekseyev_, Feb 11 2012