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A276126
a(0) = a(1) = a(2) = a(3) = a(4) = 1; for n>4, a(n) = ( a(n-1)^2+a(n-2)^2+a(n-3)^2+a(n-4)^2+a(n-1)*a(n-2)*a(n-3)*a(n-4) ) / a(n-5).
1
1, 1, 1, 1, 1, 5, 33, 1281, 1853441, 3826997739521, 2989151785658720873470945, 271581474754155314350055167823358355425497243141, 57581776430597685625970981157448022010386123824977761496513036956000541901241585948341716033
OFFSET
0,6
LINKS
FORMULA
a(n) = 10*a(n-1)*a(n-2)*a(n-3)*a(n-4) - a(n-1)*a(n-2)*a(n-3) - a(n-2)*a(n-3)*a(n-4) - a(n-3)*a(n-4)*a(n-1) - a(n-4)*a(n-1)*a(n-2) - a(n-5).
MATHEMATICA
nxt[{a_, b_, c_, d_, e_}]:={b, c, d, e, (e^2+d^2+c^2+b^2+e*d*c*b)/a}; NestList[nxt, {1, 1, 1, 1, 1}, 15][[All, 1]] (* Harvey P. Dale, Aug 08 2022 *)
PROG
(Ruby)
def A(m, n)
a = Array.new(m, 1)
ary = [1]
while ary.size < n + 1
i = a[1..-1].inject(0){|s, i| s + i * i} + a[1..-1].inject(:*)
break if i % a[0] > 0
a = *a[1..-1], i / a[0]
ary << a[0]
end
ary
end
def A276126(n)
A(5, n)
end
CROSSREFS
Sequence in context: A212296 A276160 A145505 * A193325 A303693 A256373
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 21 2016
STATUS
approved