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A294048 Permutations of [n] avoiding {2143,1432,1324}. 0
1, 1, 2, 6, 21, 77, 289, 1103, 4261, 16603, 65100, 256466, 1014107, 4021836, 15988827, 63691619, 254145940, 1015570446, 4063266013, 16274491491, 65245082548, 261786577155, 1051150840105, 4223435727598, 16979312455238, 68297061505195, 274846004875298, 1106529463859781 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..27.

D. Callan, T. Mansour, Enumeration of small Wilf classes avoiding 1324 and two other 4-letter patterns, arXiv:1705.00933 [math.CO] (2017), Table 1 No 227.

MAPLE

C := (1-sqrt(1-4*x))/2/x ;

(1 -6*x +12*x^2 -12*x^3 +6*x^4 -x^5 -x^2*(1 -x +x^2)^2*C)/(1 -7*x +16*x^2 -19*x^3 +11*x^4 -2*x^5 -x^6) ;

taylor(%, x=0, 40) ;

gfun[seriestolist](%) ;

CROSSREFS

Sequence in context: A101879 A242622 A279561 * A063023 A150188 A150189

Adjacent sequences:  A294045 A294046 A294047 * A294049 A294050 A294051

KEYWORD

nonn,easy

AUTHOR

R. J. Mathar, Nov 09 2017

STATUS

approved

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Last modified February 24 07:19 EST 2020. Contains 332199 sequences. (Running on oeis4.)