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%I #11 May 05 2024 19:30:43
%S 1,0,0,0,1,0,0,0,0,0,0,0,0,0,1,1,0,0,0,1,1,0,0,0,2,0,0,0,1,0,0,0,0,0,
%T 0,1,0,1,0,1,1,0,1,0,1,1,1,0,0,0,0,0,0,0,0,1,0,0,0,1,1,0,0,1,2,0,0,0,
%U 0,0,0,0,0,1,0,1,0,2,1,1,1,0,1,0,1,0,0,0,0,2,1,0,0,0,0,1,0,0,0,1,2,0,0,0,1
%N Number of 0's in decimal expansion of triangular number n(n+1)/2.
%H Paolo Xausa, <a href="/A086071/b086071.txt">Table of n, a(n) for n = 0..10000</a>
%e tri(4)=10, so a(4)=1 and tri(24)=300, so a(24)=2.
%t DigitCount[Accumulate[Range[0, 100]], 10, 0] (* _Paolo Xausa_, May 05 2024 *)
%Y Cf. 1's A086072, 2's A086073, 3's A086074, 4's A086075, 5's A086076, 6's A086077, 7's A086078, 8's A086079, 9's A086080.
%Y Cf. A000217.
%K base,nonn
%O 0,25
%A _Jason Earls_, Jul 08 2003