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%I #7 Jan 01 2014 23:41:34
%S 5,15,105,1035,103285,10832185,1083241785,1087326541785,
%T 108703236544918785,108870232356544491187785
%N a(1) = 5; a(n+1) = smallest triangular number > a(n) formed by adding at least one digit to a(n).
%C From a(3) onwards the sequence is A068618.
%Y Cf. A068618, A068619, A068621, A068623, A068624.
%K base,hard,more,nonn
%O 1,1
%A _Amarnath Murthy_, Feb 25 2002
%E a(6)-a(9) from _Max Alekseyev_, Apr 21 2009
%E a(10) from _Max Alekseyev_, Jan 01 2014