



1, 1, 8, 512, 262144, 1073741824, 35184372088832, 9223372036854775808, 19342813113834066795298816, 324518553658426726783156020576256, 43556142965880123323311959751266331066368
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OFFSET

0,3


COMMENTS

Sequence given by the Hankel transform (see A001906 for definition) of A082147 = {1, 1, 9, 89, 945, 10577, 123129, 1476841, ...}; example : det([1, 1, 9, 89; 1, 9, 89, 945; 9, 89, 945, 10577; 89, 945, 10577, 123129]) = 8^6 = 262144.
Hankel transform of A059435 = [1, 2, 12, 88, 720, 6304, ...] .  Philippe Deléham, Sep 03 2006
The number of labeled graphs (with no self loops) such that at most three edges connect any vertex pair.  Geoffrey Critzer, Nov 10 2011


LINKS

Table of n, a(n) for n=0..10.


FORMULA

a(n+1) is the determinant of n X n matrix M_(i, j) = binomial(8i, j).
Hankel transform of A059435 = [1, 2, 12, 88, 720, 6304, ...] .  Philippe Deléham, Sep 03 2006


MATHEMATICA

Table[2^(3*Binomial[n, 2]), {n, 0, 10}] (* Geoffrey Critzer, Nov 10 2011 *)


PROG

(PARI) a(n)=8^binomial(n, 2) \\ Charles R Greathouse IV, Jan 17 2012


CROSSREFS

Cf. A006125, A047656, A053763, A053764, A109345, A109354, A109493.
Sequence in context: A145259 A154025 A013713 * A139567 A035131 A067512
Adjacent sequences: A109963 A109964 A109965 * A109967 A109968 A109969


KEYWORD

nonn,easy


AUTHOR

Philippe Deléham, Sep 01 2005


STATUS

approved



