A006947 Two-rowed truncated monotone triangles. (Formerly M1797)

2, 7, 35, 219, 1594, 12935, 113945, 1070324, 10586856, 109259633, 1168384157, 12877168147, 145656436074, 1685157199175, 19886174611045, 238819338399054, 2913166800256664, 36036122671902718, 451429953643336590, 5720172601392931006

Offset

1,1

References

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

Table of n, a(n) for n=1..20.

W. H. Mills et al., Self-complementary totally symmetric plane partitions, J. Combin. Theory, A 42 (1986), 277-292.

D. Zeilberger, Proof of the Alternating Sign Matrix Conjecture, Electronic J. Comb., 3(2) R13, 1996.

Crossrefs

Sequence in context: A260530 A201690 A080831 * A182224 A317421 A292182

Adjacent sequences: A006944 A006945 A006946 * A006948 A006949 A006950

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

a(17)-a(21) from Sean A. Irvine, Sep 05 2017

Status

approved