0,4

Row sums are A012259(n+1). Inverse is A166318. A166318 is a signed version of A166317.

Triangle begins

1,

0, 1,

4, 0, 1,

0, 16, 0, 1,

80, 0, 40, 0, 1,

0, 640, 0, 80, 0, 1,

3904, 0, 2800, 0, 140, 0, 1,

0, 49152, 0, 8960, 0, 224, 0, 1,

354560, 0, 319744, 0, 23520, 0, 336, 0, 1,

0, 6225920, 0, 1454080, 0, 53760, 0, 480, 0, 1,

51733504, 0, 54897920, 0, 5230720, 0, 110880, 0, 660, 0, 1

Production matrix is

0, 1,

4, 0, 1,

0, 12, 0, 1,

16, 0, 24, 0, 1,

0, 80, 0, 40, 0, 1,

64, 0, 240, 0, 60, 0, 1,

0, 448, 0, 560, 0, 84, 0, 1,

256, 0, 1792, 0, 1120, 0, 112, 0, 1,

0, 2304, 0, 5376, 0, 2016, 0, 144, 0, 1

which is the exponential Riordan array [cosh(2x),x] minus its top row.

Sequence in context: A117435 A117436 A166318 this_sequence A068346 A006838 A061309

Adjacent sequences: A166314 A166315 A166316 this_sequence A166318 A166319 A166320

easy,nonn,tabl

Paul Barry (pbarry(AT)wit.ie), Oct 11 2009