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A027021 a(n) = T(n,n) + T(n,m+1) + ... + T(n,n), where m=[ (n+2)/2 ], T given by A027011. 0
1, 1, 6, 7, 36, 56, 181, 317, 826, 1531, 3576, 6832, 15021, 29201, 61966, 121727, 252796, 499816, 1024101, 2033077, 4130226, 8220851, 16609456, 33115232, 66669661, 133067881, 267285606, 533860567, 1070731476, 2139602456 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..30.

FORMULA

G.f.: x(-4x^6+10x^4-x^3-x+1)/[(1-x^2)(1-2x)(1+x-x^2)(1-x-x^2)].

CROSSREFS

Sequence in context: A037411 A025626 A175167 * A013627 A248850 A294728

Adjacent sequences:  A027018 A027019 A027020 * A027022 A027023 A027024

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified September 25 19:18 EDT 2021. Contains 347659 sequences. (Running on oeis4.)