cp's OEIS Frontend

A153753 Numbers k such that there are 18 digits in k^2 and for each factor f of 18 (1,2,3,6,9) the sum of digit groupings of size f is a square.

%I A153753 #19 May 09 2021 07:53:32
%S A153753 324344373,333306315,333321861,333359685,333361029,334363803,
%T A153753 369396732,370397193,407380269,407381484,444475035,666636972,
%U A153753 666695028,666701463,702667239,702671124,702736170,703667130,704741610
%N A153753 Numbers k such that there are 18 digits in k^2 and for each factor f of 18 (1,2,3,6,9) the sum of digit groupings of size f is a square.
%C A153753 This sequence is a subsequence of both A153745 and A061910.
%e A153753 324344373^2 = 105199272296763129;
%e A153753 1+0+5+1+9+9+2+7+2+2+9+6+7+6+3+1+2+9 = 81 = 9^2;
%e A153753 10+51+99+27+22+96+76+31+29 = 441 = 21^2;
%e A153753 105+199+272+296+763+129 = 1764 = 42^2;
%e A153753 105199+272296+763129 = 1140624 = 1068^2;
%e A153753 105199272+296763129 = 401962401 = 20049^2.
%Y A153753 Cf. A004159, A061910, A153745.
%K A153753 nonn,base,fini,full
%O A153753 1,1
%A A153753 _Doug Bell_, Dec 31 2008