login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A276267 a(n) = ( a(n-1)^2*a(n-2)^2*a(n-3)^2 + 1 ) / a(n-4), with a(0)=a(1)=a(2)=a(3)=1. 2
1, 1, 1, 1, 2, 5, 101, 1020101, 132690278976255013, 37379828474243017116309068570169440106423243719554 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,5
LINKS
MATHEMATICA
RecurrenceTable[{a[n] == (a[n - 1]^2 a[n - 2]^2 a[n - 3]^2 + 1)/a[n - 4], a[0] == a[1] == a[2] == a[3] == 1}, a, {n, 0, 10}] (* Michael De Vlieger, Aug 26 2016 *)
nxt[{a_, b_, c_, d_}]:={b, c, d, (b^2 c^2 d^2+1)/a}; NestList[nxt, {1, 1, 1, 1}, 10][[All, 1]] (* Harvey P. Dale, Nov 18 2021 *)
PROG
(Ruby)
def A(m, n)
a = Array.new(m, 1)
ary = [1]
while ary.size < n + 1
i = (a[1..-1].inject(:*)) ** 2 + 1
break if i % a[0] > 0
a = *a[1..-1], i / a[0]
ary << a[0]
end
ary
end
def A276267(n)
A(4, n)
end
CROSSREFS
Sequence in context: A027720 A132482 A208209 * A215845 A276110 A136106
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 26 2016
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 22 01:34 EDT 2024. Contains 371887 sequences. (Running on oeis4.)