1,1

Andrew Howroyd, Table of n, a(n) for n = 1..500

Index entries for linear recurrences with constant coefficients, signature (24,-245,1403,-5022,11858, -18861,19829,-12118,1011,5487, -4942,1470,543,-565,78,67,-12,-4).

G.f.: 2*x*(4 - 51*x + 256*x^2 - 660*x^3 + 1082*x^4 - 1431*x^5 + 698*x^6 + 4667*x^7 - 15736*x^8 + 23396*x^9 - 16421*x^10 + 1174*x^11 + 4664*x^12 - 1000*x^13 - 500*x^14 + 100*x^15 - 221*x^16 - 99*x^17 - 10*x^18)/((1 - x)^2*(1 - 7*x + 12*x^2 - 7*x^3 + 3*x^4 + 2*x^5)^2*(1 - 8*x + 15*x^2 - 5*x^3 - 9*x^4 + 2*x^5 + x^6)). - Andrew Howroyd, Dec 12 2024

Some solutions for n=4

...1.1.1.2.2...1.1.1.2.2...1.1.1.1.1...2.2.2.2.1...1.1.1.2.2...1.1.1.2.2

...1.1.1.1.2...1.2.2.2.1...1.2.1.1.1...2.2.1.1.1...1.2.1.1.2...1.1.1.1.2

...1.2.2.2.2...1.1.1.2.1...1.2.1.2.1...2.1.1.1.1...1.2.1.1.2...1.1.1.1.2

...1.1.1.1.2...1.1.1.1.1...1.2.2.2.2...2.2.2.2.2...1.2.2.2.2...1.1.1.1.1

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...1.1.1.1.2...2.2.2.2.2...1.1.1.1.1...1.1.2.2.2...1.1.1.2.2...1.1.1.1.1

...2.2.2.1.2...1.1.1.1.2...2.2.2.2.1...1.2.2.2.2...1.1.1.1.2...1.2.1.1.1

...2.2.2.2.2...2.2.2.2.2...1.1.1.2.1...1.2.2.1.1...1.1.1.2.2...2.2.1.1.2

...2.2.2.2.2...2.2.2.2.2...1.1.1.1.1...1.1.1.1.1...1.1.1.2.2...2.2.2.2.2

Twice row 5 of A378932.

Sequence in context: A128304 A247728 A056784 * A323960 A187667 A331512

Adjacent sequences: A166766 A166767 A166768 * A166770 A166771 A166772

nonn,easy

R. H. Hardin, Oct 21 2009

a(10) onwards from Andrew Howroyd, Dec 12 2024

approved