VOOZH about

URL: https://oeis.org/A210238

⇱ A210238 - OEIS

login
A210238
Triangle of multiplicities D(n) of multinomial coefficients corresponding to sequence A210237.
2
1, 2, 1, 3, 6, 1, 4, 12, 6, 12, 1, 5, 20, 20, 30, 30, 20, 1, 6, 30, 30, 15, 60, 120, 20, 60, 90, 30, 1, 7, 42, 42, 42, 105, 210, 105, 245, 420, 140, 105, 210, 42, 1, 8, 56, 56, 224, 28, 336, 336, 280, 168, 168, 840, 420, 1120, 70, 1120, 560, 168, 420, 56, 1
OFFSET
1,2
COMMENTS
Multiplicity D(n) of multinomial coefficient M(n) is the number of ways the same value of M(n)=n!/(m1!*m2!*..*mk!) is obtained by distributing n identical balls into k distinguishable bins.
Differs from A209936 after a(21).
Differs from A035206 after a(36).
The checksum relationship: sum(M(n)*D(n)) = k^n
The number of terms per row (for each value of n starting with n=1) forms sequence A070289.
LINKS
Sergei Viznyuk, C-program for the sequence.
EXAMPLE
1
2, 1
3, 6, 1
4, 12, 6, 12, 1
5, 20, 20, 30, 30, 20, 1
6, 30, 30, 15, 60, 120, 20, 60, 90, 30, 1
7, 42, 42, 42, 105, 210, 105, 245, 420, 140, 105, 210, 42, 1
Thus for n=3 (third row) the same value of multinomial coefficient follows from the following combinations:
3!/(3!0!0!) 3!/(0!3!0!) 3!/(0!0!3!) (i.e. multiplicity=3)
3!/(2!1!0!) 3!/(2!0!1!) 3!/(0!2!1!) 3!/(0!1!2!) 3!/(1!0!2!) 3!/(1!2!0!) (i.e. multiplicity=6)
3!/(1!1!1!) (i.e. multiplicity=1)
MATHEMATICA
Table[Last/@Tally[Multinomial@@@Compositions[k, k]], {k, 8}] (* Wouter Meeussen, Mar 09 2013 *)
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Sergei Viznyuk, Mar 18 2012
STATUS
approved