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A068621
a(1) = 7; a(n+1) = smallest triangular number > a(n) formed by adding at least one digit to a(n).
4
7, 78, 378, 1378, 91378, 7791378, 707914378, 3270729214378, 183270773294214378, 1783270773268946226147378
OFFSET
1,1
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Feb 25 2002
EXTENSIONS
a(5)-a(7) from Ray G. Opao, Dec 14 2004
a(8)-a(10) from Max Alekseyev, Apr 25 2009, Feb 11 2018
STATUS
approved