OFFSET
1,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..650
EXAMPLE
Triangle begins as:
1;
2 1;
1 2 3;
4 3 2 1;
1 2 3 4 5;
6 5 4 3 2 1;
MATHEMATICA
a[n_] := FromDigits[Join@@Table[IntegerDigits[If[EvenQ[n+1-i], n+2-2i, i]], {i, 1, Ceiling[n/2]}]]
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Feb 10 2003
STATUS
approved