login
A024437
Expansion of 1/((1-x)(1-7x)(1-8x)(1-9x)).
1
1, 25, 410, 5570, 67971, 774075, 8402620, 88071940, 898959941, 8988218525, 88404153630, 858025759110, 8237487011911, 78372461725375, 740024044725440, 6943130337867080, 64790256275839881, 601800374629166625
OFFSET
0,2
FORMULA
G.f.: 1/((1-x)(1-7x)(1-8x)(1-9x)).
a(n) = (21*9^(n+3) - 6*8^(n+4) + 4*7^(n+4) - 1)/336. - Yahia Kahloune, Jun 28 2013
a(n) = 25*a(n-1) - 215*a(n-2) + 695*a(n-3) - 504*a(n-4). - Matthew House, Jan 16 2017
CROSSREFS
Sequence in context: A028057 A260953 A025998 * A028041 A025995 A023955
KEYWORD
nonn,easy
STATUS
approved