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 A062881 Number of partitions of n^2 into exactly n nonzero parts, such that there are at most one 1's, two 2's, ... n-1 n-1's, n n's, n-1 n+1's, ... two 2n-2's and one 2n-1. 0
 1, 2, 5, 17, 66, 295, 1408, 7103, 37140, 199915, 1100752, 6174851, 35179360, 203069441, 1185443261, 6987897811, 41544411702, 248853224179, 1500635461876, 9103375030686, 55521964829070, 340282330969943, 2094756627157200 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS All monomials in "formal determinant" of Hankel matrix, (i.e., including those with zero coefficient due to cancellation). Upper bound for A019448. LINKS EXAMPLE a(3) = 5 since the 3-part partitions of 9 meeting the budget for parts (i.e., at most 1 1's, 2 2s, 3 3s, 2 4s and 1 5s) are 1+3+5, 1+4+4, 2+2+5, 2+3+4 and 3+3+3. PROG (PARI) { a(n) = polcoeff( polcoeff( prod(i=1, 2*n-1, sum(j=0, n-abs(i-n), (x^i*y)^j ) + O(x^(n^2+1)) + O(y^(n+1)) ), n^2, x ), n, y) } \\ Max Alekseyev, Jan 24 2010 CROSSREFS Cf. A019448. Sequence in context: A008932 A167809 A262449 * A122206 A104082 A166474 Adjacent sequences:  A062878 A062879 A062880 * A062882 A062883 A062884 KEYWORD nonn AUTHOR Marc LeBrun, Jun 26 2001 EXTENSIONS Corrected by Vladeta Jovovic, Jul 01 2001 Definition corrected by N. J. A. Sloane, Mar 12 2009 a(13) onward from Max Alekseyev, Jan 24 2010 STATUS approved

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Last modified January 15 20:47 EST 2019. Contains 319184 sequences. (Running on oeis4.)