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%I M1456 N0575 #19 Feb 01 2022 01:06:53
%S 0,1,2,5,14,39,109,312,890,2552,7325,21047,60465,173750,499068,
%T 1433071,4113105,11799780,33834367,96968462,277771344,795310628,
%U 2276055442,6510786627,18616389094,53207964655,152014267327,434136228215
%N Number of paraffins C_n H_{2n-1} X_3 with n carbon atoms.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%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; line 7 of Table I.
%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; Table I, line 7. (Annotated scanned copy)
%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; Table I, line 7. (Annotated scanned copy)
%F G.f.: A(x) = ((x*r)/6)*( 1/(1-x*R)^3 + 3/((1-x*R)*(1-x^2*R2)) + 2/(1-x^3*R3)); r = A000598(x), R=A000642(x)/x, Ri=R(x^i).
%K nonn,easy
%O 0,3
%A _N. J. A. Sloane_