%I #11 Nov 21 2020 17:04:46

%S 0,0,0,0,1,3,8,20,46,102,220,461,948,1921,3836,7574,14810,28705,55212,

%T 105485,200300,378262,710795,1329603,2476817,4596297,8499396,15665681,

%U 28786696,52747907,96398485,175735593,319623891,580054269

%N Used by Polya in calculating A000598.

%H G. Polya, <a href="http://dx.doi.org/10.1524/zkri.1936.93.1.415">Algebraische Berechnung der Anzahl der Isomeren einiger organischer Verbindungen</a>, Zeit. f. Kristall., 93 (1936), 415-443; q^{I}(x) on p. 441.

%H G. Polya, <a href="/A000598/a000598_3.pdf">Algebraische Berechnung der Anzahl der Isomeren einiger organischer Verbindungen</a>, Zeit. f. Kristall., 93 (1936), 415-443; q^{I}(x) on p. 441. (Annotated scanned copy)

%F G.f.: x * q(x) * (q(x)^3 - 3*q(x)*q(x^2) + 2*q(x^3)) / 6 where q(x) is the g.f. of A000621 with offset 0 [from Polya]. - _Sean A. Irvine_, Nov 21 2020

%K nonn

%O 0,6

%A _N. J. A. Sloane_.

%E a(33) corrected by _Sean A. Irvine_, Nov 21 2020