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%I #7 Dec 21 2020 07:41:35
%S 0,4,87640,206648324,206657530,206657532,206657560,206657576
%N Numbers k such that there are equal numbers of 0's and 1's and equal numbers of 2's and 3's among the first k digits of the quaternary representation of Pi.
%C There are no more terms below 2*10^9.
%e 4 is a term because the first four quaternary digits of Pi are 3, 0, 2, 1, one of each digit.
%e 87640 is a term because among the first 87640 digits there are 21880 0's, 21880 1's, 21940 2's and 21940 3's.
%Y Cf. A004603, A039624, A339449.
%K nonn,base,more
%O 1,2
%A _Pontus von Brömssen_, Dec 05 2020