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A026380 a(n) = T(n,[ n/2 ]), where T is the array in A026374. 2
1, 3, 4, 11, 17, 45, 75, 195, 339, 873, 1558, 3989, 7247, 18483, 34016, 86515, 160795, 408105, 764388, 1936881, 3650571, 9238023, 17501619, 44241261, 84179877, 212601015, 406020930, 1024642875, 1963073865, 4950790605 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..29.

D. E. Davenport, L. W. Shapiro and L. C. Woodson, The Double Riordan Group, The Electronic Journal of Combinatorics, 18(2) (2012), #P33. - From N. J. A. Sloane, May 11 2012

FORMULA

a(2n)=A026378(n+1), a(2n-1)=A026375(n). - Emeric Deutsch, Feb 18 2004

a(2n) = A026378(2n+1), a(2n+1) = A026375(n+1).

Davenport et al. give a g.f.

CROSSREFS

Cf. A026375, A026378.

Sequence in context: A231882 A026753 A027222 * A030225 A060285 A025079

Adjacent sequences:  A026377 A026378 A026379 * A026381 A026382 A026383

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified October 13 18:57 EDT 2019. Contains 327981 sequences. (Running on oeis4.)