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A321634 Number of arrangements of n 1's, n 2's, ..., n n's avoiding equal consecutive terms. 3
1, 1, 2, 174, 2265024, 7946203275000, 12229789732207993835280, 12202002913678756821228939869239920, 10937192762438008527903830198163831816546577931520, 11655577382287102750765311537460065620507094071664576111302628243840 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
Mathematics.StackExchange, Find the number of k 1's, k 2's, ... , k n's - total kn cards, Apr 08 2012.
FORMULA
a(n) ~ n^(n^2 - n/2 + 1) / ((2*Pi)^((n-1)/2) * exp(n - 5/12)). - Vaclav Kotesovec, Nov 24 2018
PROG
(PARI) {a(n) = sum(i=n, n^2, i!*polcoef(sum(j=1, n, (-1)^(n-j)*binomial(n-1, j-1)*x^j/j!)^n, i))} \\ Seiichi Manyama, May 27 2019
CROSSREFS
Sequence in context: A360478 A193638 A215123 * A219724 A103427 A216355
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Nov 15 2018
STATUS
approved

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Last modified March 5 02:44 EST 2024. Contains 370537 sequences. (Running on oeis4.)