A155052 Image of symmetric Catalan based triangle A155050 under ((1+x)/(1-x),x)^{-1}.

1, -1, 1, 1, -1, 1, -1, 1, -1, 1, 1, -1, 2, -1, 1, -1, 1, -2, 2, -1, 1, 1, -1, 2, 1, 2, -1, 1, -1, 1, -2, -1, 1, 2, -1, 1, 1, -1, 2, 1, 8, 1, 2, -1, 1, -1, 1, -2, -1, -8, 8, 1, 2, -1, 1, 1, -1, 2, 1, 8, 20, 8, 1, 2, -1, 1

Offset

0,13

Comments

Row sums are aerated Catalan numbers (A000108).

Links

Table of n, a(n) for n=0..65.

Example

Triangle begins
1,
-1, 1,
1, -1, 1,
-1, 1, -1, 1,
1, -1, 2, -1, 1,
-1, 1, -2, 2, -1, 1,
1, -1, 2, 1, 2, -1, 1,
-1, 1, -2, -1, 1, 2, -1, 1,
1, -1, 2, 1, 8, 1, 2, -1, 1,
-1, 1, -2, -1, -8, 8, 1, 2, -1, 1,
1, -1, 2, 1, 8, 20, 8, 1, 2, -1, 1

Crossrefs

Sequence in context: A062831 A037828 A030419 * A096284 A163100 A139038

Adjacent sequences: A155049 A155050 A155051 * A155053 A155054 A155055

Keyword

sign,tabl

Author

Paul Barry, Jan 19 2009

Status

approved