login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A276280
Number of triangular partitions of n of order 9.
1
1, 9, 45, 173, 567, 1654, 4422, 11040, 26051, 58638, 126778, 264670, 535806, 1055480, 2028884, 3814688, 7029559, 12717703, 22622719, 39618458, 68384638, 116456100, 195837008, 325462408, 534921468, 870044724, 1401226327, 2235733481, 3535790660
OFFSET
0,2
LINKS
L. Carlitz, R. Scoville, A generating function for triangular partitions, Math. Comp. 29 (1975) 67-77.
FORMULA
G.f.: 1/((1-x)^9*(1-x^3)^8*(1-x^5)^7*(1-x^7)^6*(1-x^9)^5*(1-x^11)^4*(1-x^13)^3*(1-x^15)^2*(1-x^17)).
MATHEMATICA
CoefficientList[Series[1/((1-x)^9 (1-x^3)^8 (1-x^5)^7 (1-x^7)^6 (1-x^9)^5 (1-x^11)^4 (1-x^13)^3 (1-x^15)^2 (1-x^17)), {x, 0, 50}], x]
PROG
(Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)^9*(1-x^3)^8*(1-x^5)^7*(1-x^7)^6*(1-x^9)^5*(1-x^11)^4*(1-x^13)^3*(1-x^15)^2*(1-x^17))));
CROSSREFS
Cf. similar sequences listed in A276235.
Sequence in context: A221142 A144902 A128643 * A036826 A022574 A321948
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Sep 01 2016
STATUS
approved