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A051287 Triangular array T read by rows: T(n,k)=P(n,k,|n-2k|), where P(n,k,c)=number of vectors (x(1),x(2,),...,x(n)) of k 1's and n-k 0's such that x(i)=x(n+1-i) for exactly c values of i. 0
1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 4, 4, 4, 1, 1, 4, 4, 4, 4, 1, 1, 6, 12, 8, 12, 6, 1, 1, 6, 12, 8, 8, 12, 6, 1, 1, 8, 24, 32, 16, 32, 24, 8, 1, 1, 8, 24, 32, 16, 16, 32, 24, 8, 1, 1, 10, 40, 80, 80, 32, 80, 80, 40, 10, 1, 1, 10, 40, 80, 80, 32, 32, 80 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

P(n,k,n) counts palindromes.

LINKS

Table of n, a(n) for n=0..73.

EXAMPLE

Rows: {1}; {1,1}; {1,2,1}; ...

CROSSREFS

Sequence in context: A176653 A174842 A156074 * A278218 A216031 A263985

Adjacent sequences:  A051284 A051285 A051286 * A051288 A051289 A051290

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified April 25 08:06 EDT 2018. Contains 303048 sequences. (Running on oeis4.)