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A374553
Number of length n inversion sequences avoiding the patterns 010 and 102.
2
1, 1, 2, 5, 15, 51, 186, 707, 2763, 11024, 44714, 183830, 764374, 3209031, 13584217, 57918257, 248502212, 1072159593, 4648747281, 20245772943, 88524364619, 388469248937, 1710304847176, 7552480937589, 33442335151831, 148456424569164, 660560252794208
OFFSET
0,3
LINKS
FORMULA
Conjecture: G.f. F(x) is algebraic with minimal polynomial x * (x^2 - x + 1)*(x - 1)^2 * F(x)^3 + 2*x*(x - 1)*(2*x^2 - 2*x + 1)*F(x)^2 - (x^4 - 8*x^3 + 11*x^2 - 6*x + 1)*F(x) - (2*x - 1)*(x - 1)^2.
CROSSREFS
KEYWORD
nonn
AUTHOR
Benjamin Testart, Jul 17 2024
STATUS
approved