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A025570 a(n) = T(2n,n), where T is the array defined in A025564. 0
1, 2, 8, 40, 211, 1148, 6369, 35816, 203424, 1164228, 6703372, 38785840, 225325940, 1313494396, 7679038865, 45006411960, 264357297375, 1555762562100, 9171399730944, 54148782940112, 320136500713070, 1895036382245032, 11230166960501463, 66619011999761208, 395563260817743219 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..25.

CROSSREFS

Sequence in context: A076625 A139415 A119817 * A227081 A113449 A234938

Adjacent sequences:  A025567 A025568 A025569 * A025571 A025572 A025573

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

More terms from Sean A. Irvine, Sep 07 2019

STATUS

approved

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Last modified December 8 14:38 EST 2019. Contains 329865 sequences. (Running on oeis4.)