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Sub-Kaprekar numbers (1): n such that n=q-r and n^2=q*10^m+r, for some m>=1, q>=0, 0<=r<10^m, with n not a power of 10.
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%I #2 Mar 30 2012 17:40:41

%S 11,101,1001,1078,1287,1364,10001,11096,100001,118183,1000001,1336634,

%T 10000001,12727274,100000001,123529412,1000000001,1019138757,

%U 1025974026,1097744361,1120879122,1140017878,1165991904,1237762239,1288553552

%N Sub-Kaprekar numbers (1): n such that n=q-r and n^2=q*10^m+r, for some m>=1, q>=0, 0<=r<10^m, with n not a power of 10.

%e 1287^2 = 1656369 and 1656-369 = 1287.

%e A larger example: 1594563333^2 = 2542632222948068889 and

%e 2542632222-948068889=1594563333.

%Y Cf. A006886, A118936, A118938.

%K base,nonn

%O 1,1

%A _Giovanni Resta_, May 06 2006