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%I #14 Sep 11 2017 02:36:20
%S 1,1,3,3,7,8,14,18,28,35,53,66,92,117,157,196,259,319,411,507,638,777,
%T 970,1171,1438,1728,2098,2501,3012,3563,4251,5008,5923,6931,8152,9486,
%U 11078,12835,14900,17177,19844,22768,26169,29916,34219,38954,44387,50338
%N Number of partitions p of n such that max(p)-min(p) = 9.
%H Alois P. Heinz, <a href="/A218572/b218572.txt">Table of n, a(n) for n = 11..1000</a>
%H G. E. Andrews, M. Beck and N. Robbins, <a href="https://arxiv.org/abs/1406.3374">Partitions with fixed differences between largest and smallest parts</a>, arXiv:1406.3374 [math.NT], 2014.
%F G.f.: Sum_{k>0} x^(2*k+9)/Product_{j=0..9} (1-x^(k+j)).
%F a(n) = A097364(n,9) = A116685(n,9) = A194621(n,9) - A194621(n,8) = A218511(n) - A218510(n).
%t terms = 48; offset = 11; max = terms + offset; s[k0_ /; k0 > 0] := Sum[x^(2*k + k0)/Product[ (1 - x^(k + j)), {j, 0, k0}], {k, 1, Ceiling[max/2]}] + O[x]^max // CoefficientList[#, x] &; Drop[s[9], offset] (* _Jean-François Alcover_, Sep 11 2017, after _Alois P. Heinz_ *)
%K nonn
%O 11,3
%A _Alois P. Heinz_, Nov 02 2012