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%I A077487 #8 Dec 05 2013 19:55:52
%S A077487 1,4,9,16,25,36,49,64,81,100,144,196,400,441,841,900,1369,3364,4096,
%T A077487 5041,8649,10000,10816,11449,20164,38416,40000,61009,64009,90000,
%U A077487 1000000,1004004,3013696,3108169,4000000,4004001,9000000,100000000
%N A077487 Squares which leave a square at every step if most significant digit and least significant digit are deleted until a one-digit or two-digit square is obtained.
%C A077487 Sequence is infinite with nontrivial terms (10^(2k+1)+2)^2 and (2*10^(2k+1)+1)^2. - _Ray Chandler_, Aug 03 2003
%e A077487 38416 is a member as 38416, 841 and 4 all are squares.
%o A077487 (PARI) l=listcreate(1000); for(n=0,9,listput(l,n^2)); for(k=3,50, for(d1=1,9, for(n=1,length(l), for(d2=0,9,t1=l[n]; if(t1<10^(k-2),c=d1*10^(k-1) + t1*10 + d2; if(issquare(c),listput(l,c); ); ); ); ); ); ); l
%Y A077487 Cf. A077485, A077486.
%K A077487 base,nonn
%O A077487 1,2
%A A077487 _Amarnath Murthy_, Nov 07 2002
%E A077487 Corrected and extended by _Ray Chandler_, Aug 03 2003

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