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A274083 Number of unrooted labeled trees on 4n+2 nodes with node degree either one or five. 1
1, 6, 3150, 12612600, 192972780000, 8046096548490000, 747480957758835300000, 135330984231708815550000000, 43401712634861734607093640000000, 22953694145310867501311470722000000000, 18935469872719334117190133449041218500000000 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
There are no unrooted labeled trees on 4n or 4n+1 or 4n+3 nodes with node degree either one or five.
LINKS
Math.Stackexchange.com, Marko Riedel et al., Number of labeled trees
MAPLE
seq(binomial(4*n+2, n)*(4*n)!/4!^n, n=0..20);
MATHEMATICA
Table[Binomial[4*n+2, n]*(4*n)!/(4!)^n, {n, 0, 10}] (* G. C. Greubel, Jun 09 2016 *)
CROSSREFS
Sequence in context: A114184 A093884 A265869 * A079183 A373236 A030245
KEYWORD
nonn
AUTHOR
Marko Riedel, Jun 09 2016
STATUS
approved

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Last modified June 21 23:48 EDT 2024. Contains 373560 sequences. (Running on oeis4.)