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A348707
Number of tree polyominoes with width 4 and height n.
1
1, 22, 243, 2024, 14981, 104946, 716045, 4816620, 32149313, 213645182, 1416316877, 9376424198, 62027820325, 410158517056, 2711528337463, 17923333338880, 118465285682767, 782970312006472, 5174749541752549, 34200123937114224, 226028308969773551, 1493812891834066696
OFFSET
1,2
LINKS
Maxime Samson, Valence de graphes et polyominos arbres, Mémoire, Trois-Rivières, Université du Québec à Trois-Rivières, 152 p., 2020.
Index entries for linear recurrences with constant coefficients, signature (15, -74, 86, 523, -2461, 4161, 681, -17782, 40652, -50933, 23841, 65154, -202154, 306084, -279336, 135024, -16128, -9216, 2304).
FORMULA
G.f.: (x + 7*x^2 - 13*x^3 - 79*x^4 + 188*x^5 + 64*x^6 - 723*x^7 + 831*x^8 - 335*x^9 + 185*x^10 + 2890*x^11 - 5272*x^12 - 192*x^13+4008*x^14 - 9368*x^15 + 10728*x^16 + 1680*x^17 - 1824*x^18 - 576*x^19)/((1 - 2*x)*(1 - 5*x + 4*x^2 + 7*x^3 - 21*x^4 + 24*x^5 - 6*x^6)*(1 - 8*x + 4*x^2 + 55*x^3 - 167*x^4 + 180*x^5 + 214*x^6 - 653*x^7 + 1232*x^8 - 2428*x^9 + 1968*x^10 - 96*x^11 - 192*x^12)).
CROSSREFS
Cf. A348663.
Sequence in context: A249086 A300624 A249087 * A249088 A249089 A249090
KEYWORD
nonn,easy
AUTHOR
Maxime Samson, Oct 30 2021
STATUS
approved