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A360198
Number of induced cycles in the 5 X n grid graph.
2
0, 4, 14, 58, 229, 749, 2180, 6188, 17912, 52620, 154383, 450195, 1309452, 3811888, 11110432, 32392550, 94412963, 275116777, 801676752, 2336222946, 6808405238, 19841419978, 57821971765, 168504312515, 491055599116, 1431039769316, 4170353383134, 12153282490316, 35417189532323
OFFSET
1,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (6,-14,17,-3,-17,16,-2,9,-27,5,19,-3,-2,-5,2).
FORMULA
G.f.: x^2*(4 - 10*x + 30*x^2 + 9*x^3 - 39*x^4 + 16*x^5 + 49*x^6 + 28*x^7 - 76*x^8 - 58*x^9 + 7*x^10 + 13*x^11 + 9*x^12 - 4*x^13)/((1 - x)^2*(1 - 4*x + 5*x^2 - 3*x^3 - 8*x^4 + 4*x^5 - 2*x^7 - 13*x^8 + 3*x^9 + 14*x^10 + 6*x^11 + x^12 - 2*x^13)).
CROSSREFS
Row 5 of A360196.
Sequence in context: A325929 A134826 A096242 * A296943 A104987 A149492
KEYWORD
nonn,easy
AUTHOR
Andrew Howroyd, Jan 29 2023
EXTENSIONS
Missing a(1)=0 inserted by Andrew Howroyd, Feb 23 2023
STATUS
approved