(MAGMAMagma) I:=[6, 10]; [2] cat [n le 2 select I[n] else 3*Self(n-1) + 4*Self(n-2): n in [1..49]]; // G. C. Greubel, Nov 23 2018
(MAGMAMagma) I:=[6, 10]; [2] cat [n le 2 select I[n] else 3*Self(n-1) + 4*Self(n-2): n in [1..49]]; // G. C. Greubel, Nov 23 2018
editing
approved
2, 6, 10, 54, 202, 822, 3274, 13110, 52426, 209718, 838858, 3355446, 13421770, 53687094, 214748362, 858993462, 3435973834, 13743895350, 54975581386, 219902325558, 879609302218, 3518437208886, 14073748835530, 56294995342134, 225179981368522, 900719925474102
a(n) = 3*a(n-1) + 4*a(n-2), with a(0) = 2, a(1) = 6, a(2) = 10.
approved
editing
a(n) = 3*a(n-1) + 4*a(n-2), with a(-1) = 3, a(0) = -2, a(1) = 6.
3, -2, 6, 10, 54, 202, 822, 3274, 13110, 52426, 209718, 838858, 3355446, 13421770, 53687094, 214748362, 858993462, 3435973834, 13743895350, 54975581386, 219902325558, 879609302218, 3518437208886, 14073748835530, 56294995342134
-1,0,1
a(n) = (-2*(7*(-1)^n - 2^(1 + 2*n)))/5 for n >= -1 0.
a(n) = 3*a(n-1) + 4*a(n-2) for n > 02.
From Paul Curtz, May 10 2022: (Start)
a(n-1) + a(n) = 4^n for n >= 0. (End)
Cf. A000302.
sign,nonn,easy,changed
editing
approved
proposed
editing
editing
proposed
a(n) = 3*a(n-1) + 4*a(n-2), with a(-1) = 3, a(0) = -2, a(1) = 6.
3, -2, 6, 10, 54, 202, 822, 3274, 13110, 52426, 209718, 838858, 3355446, 13421770, 53687094, 214748362, 858993462, 3435973834, 13743895350, 54975581386, 219902325558, 879609302218, 3518437208886, 14073748835530, 56294995342134
0,-1,1
a(n) = (-2*(7*(-1)^n - 2^(1 + 2*n)))/5 for n >= 0-1.
a(n) = 3*a(n-1) + 4*a(n-2) for n > 10.
a(-1) =3.
a(n-1) + a(n) = 4^n for n >= 0. (endEnd)
proposed
editing
editing
proposed
a(n) = 3*a(n-1) + 4*a(n-2), with a(0) = -2, a(1) = 6.
-2, 6, 10, 54, 202, 822, 3274, 13110, 52426, 209718, 838858, 3355446, 13421770, 53687094, 214748362, 858993462, 3435973834, 13743895350, 54975581386, 219902325558, 879609302218, 3518437208886, 14073748835530, 56294995342134
a(n) = (-2*(7*(-1)^n - 2^(1 + 2*n)))/5 for n > = 0.
a(n) = 3*a(n-1) + 4*a(n-2) for n > 2.1
From Paul Curtz, May 10 2022: (Start)
a(-1) =3.
a(n-1) + a(n) = 4^n for n >= 0. (end)
Cf. A000302.
nonn,sign,easy
approved
editing