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A048828 Number of identity (asymmetric) trees of width n. 1
1, 0, 0, 0, 0, 1, 4, 66, 65328, 2146402440 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

LINKS

Table of n, a(n) for n=0..9.

Index entries for sequences related to trees

FORMULA

a(2n) = 2^(c(n-2))*(2^b(n-1) - b(n-1)-1), a(2n+1) = b(n)*(b(n)-1)/2, b: A038081. c: A014221.

CROSSREFS

Sequence in context: A302657 A198893 A279886 * A225940 A003360 A225772

Adjacent sequences:  A048825 A048826 A048827 * A048829 A048830 A048831

KEYWORD

nonn

AUTHOR

Christian G. Bower, Jun 15 1999

STATUS

approved

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Last modified February 17 17:59 EST 2020. Contains 331999 sequences. (Running on oeis4.)