OFFSET
0,1
FORMULA
a(n) = floor(a(n-1)^2/a(n-2)), a(0) = 4, a(1) = 14.
Conjectures: (Start)
G.f.: (4 - 2*x + x^2 - x^3)/(1 - 4*x + 2*x^2 - x^3 + x^4).
a(n) = 4*a(n-1) - 2*a(n-2) + a(n-3) - a(n-4). (End)
MATHEMATICA
RecurrenceTable[{a[0] == 4, a[1] == 14, a[n] == Floor[a[n - 1]^2/a[n - 2]]}, a, {n, 27}]
PROG
(PARI) first(n)=my(v=vector(n+1)); v[1]=4; v[2]=14; for(i=3, #v, v[i]=v[i-1]^2\v[i-2]); v \\ Charles R Greathouse IV, Nov 28 2016
(Python)
from itertools import islice
def A278692_gen(): # generator of terms
a, b = 4, 14
yield from (a, b)
while True:
a, b = b, b**2//a
yield b
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Ilya Gutkovskiy, Nov 28 2016
STATUS
approved