cp's OEIS Frontend

Empirical: a(n) = 26*a(n-1) for n>2

Empirical: a(n) = 76*a(n-1) - 36*a(n-2) for n>3.

Empirical g.f.: x*(14 - 47*x + 18*x^2) / (1 - 76*x + 36*x^2). - Colin Barker, Jul 02 2018

Empirical: a(n) = 222*a(n-1) - 612*a(n-2) + 432*a(n-3) for n>4.

Empirical g.f.: x*(41 - 264*x + 792*x^2 - 540*x^3) / (1 - 222*x + 612*x^2 - 432*x^3). - Colin Barker, Jul 02 2018

Empirical: a(n) = 649*a(n-1) -8088*a(n-2) +32724*a(n-3) -69156*a(n-4) +80352*a(n-5) -46656*a(n-6) for n>7

Empirical: a(n) = 1899*a(n-1) -96485*a(n-2) +1863135*a(n-3) -19545624*a(n-4) +128977488*a(n-5) -573780996*a(n-6) +1774673712*a(n-7) -3625252848*a(n-8) +3358392192*a(n-9) +1063196928*a(n-10) for n>12

Empirical: a(n) = 8*a(n-1) + 6*a(n-2) for n>4.

Conjectures from Colin Barker, Jul 02 2018: (Start)

G.f.: x*(1 + x)*(2 - 4*x - 3*x^2) / (1 - 8*x - 6*x^2).

a(n) = ((4-sqrt(22))^n*(-2+sqrt(22)) + (2+sqrt(22))*(4+sqrt(22))^n) / (8*sqrt(22)) for n>2.

(End)

Empirical: a(n) = 22*a(n-1) + 80*a(n-2) + 40*a(n-3) - 48*a(n-4) for n>6.

Empirical g.f.: x*(5 + 12*x - 42*x^2 - 78*x^3 + 4*x^4 + 24*x^5) / ((1 + 2*x)*(1 - 24*x - 32*x^2 + 24*x^3)). - Colin Barker, Jul 02 2018

Empirical: a(n) = 61*a(n-1) +868*a(n-2) +2200*a(n-3) -7744*a(n-4) -17728*a(n-5) +40704*a(n-6) -13824*a(n-7) for n>9.

Empirical: a(n) = 171*a(n-1) +8504*a(n-2) +77860*a(n-3) -1000900*a(n-4) -11005932*a(n-5) +78914544*a(n-6) +374284064*a(n-7) -3897108352*a(n-8) +9817487872*a(n-9) -6449426432*a(n-10) -6696632320*a(n-11) +7534936064*a(n-12) +1817837568*a(n-13) -2092433408*a(n-14) -484442112*a(n-15) for n>18