login
Numbers k such that there are 12 digits in k^2 and for each factor f of 12 (1,2,3,4,6) the sum of digit groupings of size f is a square.
1

%I #14 May 09 2021 07:53:02

%S 316713,334401,658635

%N Numbers k such that there are 12 digits in k^2 and for each factor f of 12 (1,2,3,4,6) the sum of digit groupings of size f is a square.

%C This is the complete sequence. This sequence is a subsequence of both A153745 and A061910.

%e 316713^2 = 100307124369;

%e 1+0+0+3+0+7+1+2+4+3+6+9 = 36 = 6^2;

%e 10+03+07+12+43+69 = 144 = 12^2;

%e 100+307+124+369 = 900 = 30^2;

%e 1003+0712+4369 = 6084 = 78^2;

%e 100307+124369 = 224676 = 474^2.

%Y Cf. A061910, A153745.

%K nonn,base,fini,bref,full

%O 1,1

%A _Doug Bell_, Dec 31 2008