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%I #12 Dec 01 2021 05:33:10
%S 1,3,6,10,21,15,28,36,45,66,55,78,91,105,210,136,253,120,231,153,276,
%T 190,325,171,300,435,351,406,378,465,528,496,561,630,595,666,703,820,
%U 741,903,780,861,946,1035,990,1081,2145,1326,2080,1128,2016,1225,2346
%N a(1) = 1; a(n) is the smallest triangular number not already in the sequence which differs from a(n-1) at every digit.
%e 136 follows 210 as the smallest triangular number not included earlier and differing at every digit position with 210.
%Y Cf. A000217, A068855.
%K nonn,base
%O 1,2
%A _Amarnath Murthy_, Mar 13 2002
%E Corrected and extended by _Sascha Kurz_, Feb 02 2003