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%I #5 Dec 05 2013 19:55:56
%S 1,25,3025,48400,5856400,6377619600,771691971600,840372557072400,
%T 915165714651843600,1057931566137531201600,1152087475523771478542400,
%U 1254623260845387140132673600,1366284731060626595604481550400
%N a(1) = 1; a(n) for n > 1 is the smallest multiple of a(n-1) that is a square and begins with n.
%e For n = 3 we have a(n-1) = a(2) = 25; 121*25 = 3025 is the smallest multiple of 25 that is a square and begins with 3, so a(3) = 3025.
%o (PARI) {print1(a=1,","); for(n=2,13,k=floor(log(a)/log(10))+1; s=n; t=s+1; m=floor(log(s)/log(10))+1; d=k-m; s=s*10^d; t=t*10^d; b=1; while(b>0,q=floor(s/a); while(b>0&&(p=q*a)<t,if(p>=s&&issquare(p),print1(p,","); b=0,q++)); s=10*s; t=10*t); a=p)}
%Y Cf. A078216, A078815.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 22 2002
%E Edited and extended by _Klaus Brockhaus_, Dec 06 2002
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