

A198890


Irregular triangle read by rows: row n gives expansion of g.f. for descending plane partitions of order n with weight equal to sum of the parts.


0



1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 2, 2, 2, 3, 2, 4, 3, 4, 4, 4, 5, 4, 5, 5, 4, 6, 4, 5, 5, 4, 5, 4, 4, 4, 3, 4, 2, 3, 2, 2, 2, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 2, 3, 2, 4, 3, 5, 5, 7, 6, 8, 8, 9, 10, 12, 10, 14, 12, 14, 15, 16, 15, 18, 16, 18, 18, 20, 17, 21, 18, 20, 20, 20, 18, 21, 17, 20, 18, 18, 16, 18, 15, 16, 15, 14, 12, 14, 10, 12, 10, 9, 8, 8, 6, 7, 5, 5, 3, 4, 2, 3, 2, 1, 1, 1, 0, 1
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OFFSET

1,20


REFERENCES

J. Striker, A direct bijection between descending plane partitions ..., Discrete Math., 311 (2011),25812585.


LINKS

Table of n, a(n) for n=1..146.


EXAMPLE

Rows 1 through 5 are
1
1, 0, 1
1, 0, 1, 1, 0, 1, 1, 0, 1
1, 0, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 0, 1
1, 0, 1, 1, 1, 2, 2, 2, 3, 2, 4, 3, 4, 4, 4, 5, 4, 5, 5, 4, 6, 4, 5, 5, 4, 5, 4, 4, 4, 3, 4, 2, 3, 2, 2, 2, 1, 1, 1, 0, 1


MAPLE

s:=(k, q)>add(q^i, i=0..k1);
f:=n>mul(s(i, q^i), i=1..n);
g:=n>seriestolist(series(f(n), q, 1000));
for n from 1 to 10 do lprint(g(n)); od:


CROSSREFS

Sequence in context: A140195 A196564 A196563 * A305831 A022927 A063435
Adjacent sequences: A198887 A198888 A198889 * A198891 A198892 A198893


KEYWORD

nonn,tabf


AUTHOR

N. J. A. Sloane, Oct 30 2011


STATUS

approved



