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A005955 Number of acyclic secondary alcohols with n carbon atoms.
(Formerly M1453)
0
1, 2, 5, 14, 36, 98, 273, 768, 2197, 6360, 18584, 54780, 162672, 486154, 1461197, 4413988, 13393855, 40807290, 124783669, 382842018, 1178140280, 3635626680, 11247841224, 34880346840, 108402132544, 337576497920, 1053229358252, 3291813720292 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=3..30.

R. C. Read, The Enumeration of Acyclic Chemical Compounds, pp. 25-61 of A. T. Balaban, ed., Chemical Applications of Graph Theory, Ac. Press, 1976. [Annotated scanned copy] See p. 44.

FORMULA

G.f. x*(B(x)-1)^2 where B(x) is the g.f. for A000625. - Sean A. Irvine, Nov 12 2016

EXAMPLE

G.f. = x^3 + 2*x^4 + 5*x^5 + 14*x^6 + 36*x^7 + 98*x^8 + 273*x^9 + ...

CROSSREFS

Cf. A000625.

Sequence in context: A182890 A102714 A087223 * A186903 A062197 A030016

Adjacent sequences:  A005952 A005953 A005954 * A005956 A005957 A005958

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Sean A. Irvine, Nov 12 2016

STATUS

approved

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Last modified November 17 03:06 EST 2019. Contains 329216 sequences. (Running on oeis4.)