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A211505
Number of solid standard Young tableaux of shape [[(3)^n],[3]].
2
5, 192, 5471, 143164, 3636776, 91442364, 2293620329, 57583680440, 1449149180310, 36577522323264, 926132803592304, 23521922685452320, 599176262762762880, 15305331537941936820, 391972832520910172865, 10062682947669846370800, 258904473727824391312650
OFFSET
1,1
COMMENTS
a(n) is odd if and only if n = 2^k-1, k in {1, 2, 3, ... }.
LINKS
S. B. Ekhad, D. Zeilberger, Computational and Theoretical Challenges on Counting Solid Standard Young Tableaux, arXiv:1202.6229v1 [math.CO], 2012
Wikipedia, Young tableau
FORMULA
a(n) = (600 + 2874*n + 4709*n^2 + 3246*n^3 + 1019*n^4 + 144*n^5 + 8*n^6)*(2+3*n)! / (2*(3+2*n)*(5+2*n)*(n-1)!*(2+n)!*(5+n)!). - Vaclav Kotesovec, Jul 16 2014
MAPLE
a:=proc(n) option remember; `if`(n<3, [5, 192][n],
((-300307980720421134*n^6 -450257143569814251*n^5 +520721206232593545*n^4
+237675576478617990*n^3 -244917832991741721*n^2 +20947752092648421*n
+7263907687560150)*a(n-2) +(20284627624231332*n^6 +74969736339564876*n^5
-90577816139486502*n^4 -578021108537112633*n^3 -713543105276625459*n^2
-309855589348004634*n -29055630750240600)*a(n-1)) / (339337400732270*n^6
+2086412513047793*n^5 -1761594949059583*n^4 -24340927184757907*n^3
-25005499944921313*n^2 +25705682578023740*n +29939073413286900))
end:
seq(a(n), n=1..20);
MATHEMATICA
Table[(600 + 2874*n + 4709*n^2 + 3246*n^3 + 1019*n^4 + 144*n^5 + 8*n^6)*(2+3*n)! / (2*(3+2*n)*(5+2*n)*(n-1)!*(2+n)!*(5+n)!), {n, 1, 20}] (* Vaclav Kotesovec, Jul 16 2014 *)
CROSSREFS
Row n=3 of A214722.
Cf. A000225.
Sequence in context: A316330 A015102 A086124 * A198485 A177192 A100760
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Aug 06 2012
STATUS
approved