OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
41 is a term because 41 + 4 = 45, a triangular number.
MATHEMATICA
nldnQ[n_]:=IntegerQ[(Sqrt[8(n+Max[IntegerDigits[n]])+1]-1)/2]; Select[ Range[0, 2000], nldnQ] (* Harvey P. Dale, May 29 2012 *)
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Jason Earls, Jul 10 2004
STATUS
approved