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A127631 Square of Riordan array (1,xc(x)) where c(x) is the g.f. of A000108. 1
1, 0, 1, 0, 2, 1, 0, 6, 4, 1, 0, 21, 16, 6, 1, 0, 80, 66, 30, 8, 1, 0, 322, 280, 143, 48, 10, 1, 0, 1348, 1216, 672, 260, 70, 12, 1, 0, 5814, 5385, 3150, 1344, 425, 96, 14, 1, 0, 25674, 24244 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Square of A106566. Row sums are A127632.

LINKS

Table of n, a(n) for n=0..47.

FORMULA

Riordan array (1,x*c(x)*c(x*c(x)))

T(n+1,1) = A129442(n) = A121988(n+1). - Philippe Deléham, Feb 27 2013

EXAMPLE

Triangle begins

1,

0, 1,

0, 2, 1,

0, 6, 4, 1,

0, 21, 16, 6, 1,

0, 80, 66, 30, 8, 1,

0, 322, 280, 143, 48, 10, 1,

0, 1348, 1216, 672, 260, 70, 12, 1,

0, 5814, 5385, 3150, 1344, 425, 96, 14, 1,

0, 25674, 24244, 14799, 6784, 2400, 646, 126, 16, 1,

0, 115566, 110704, 69828, 33814, 13002, 3960, 931, 160, 18, 1

CROSSREFS

Cf. A106566, A121988, A129442.

Sequence in context: A275328 A147720 A205813 * A122538 A090238 A047922

Adjacent sequences:  A127628 A127629 A127630 * A127632 A127633 A127634

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry, Jan 20 2007

STATUS

approved

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Last modified October 22 10:57 EDT 2018. Contains 316437 sequences. (Running on oeis4.)