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A215546
Number of standard Young tableaux of shape [6n,6].
2
0, 132, 9996, 92092, 451269, 1570800, 4395118, 10559208, 22664655, 44602348, 81921840, 142247364, 235740505, 375609528, 578665362, 865924240, 1263256995, 1802085012, 2520122836, 3462167436, 4680934125, 6237939136, 8204428854, 10662355704, 13705400695
OFFSET
0,2
COMMENTS
Also the number of binary words with 6n 1's and 6 0's such that for every prefix the number of 1's is >= the number of 0's.
LINKS
FORMULA
G.f.: (5*x^6-35*x^5-609*x^4-11921*x^3-24892*x^2-9072*x-132)*x/(x-1)^7.
a(n) = (6*n-5)*(6*n+5)*(3*n+2)*(2*n+1)*(3*n+1)*(n+1)/10 for n>0, a(0) = 0.
Sum_{n>=1} 1/a(n) = 76/385 - 1559*Pi/(924*sqrt(3)) + 2080*log(2)/231 - 135*log(3)/44. - Amiram Eldar, Aug 29 2025
MAPLE
a:= n-> max(0, (6*n-5)*(6*n+5)*(3*n+2)*(2*n+1)*(3*n+1)*(n+1)/10):
seq(a(n), n=0..40);
PROG
(PARI) a(n)=if(n, (648*n^6-585*n^3-928*n^2-375*n)/10+162*n^5+99*n^4-5, 0) \\ Charles R Greathouse IV, May 30 2026
CROSSREFS
Row n=6 of A214776.
Sequence in context: A184893 A035818 A258394 * A269042 A216787 A239817
KEYWORD
nonn,easy,changed
AUTHOR
Alois P. Heinz, Aug 16 2012
STATUS
approved