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%I #24 Aug 08 2022 18:52:07
%S 1,1,1,1,1,5,33,1281,1853441,3826997739521,2989151785658720873470945,
%T 271581474754155314350055167823358355425497243141,
%U 57581776430597685625970981157448022010386123824977761496513036956000541901241585948341716033
%N 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).
%H Seiichi Manyama, <a href="/A276126/b276126.txt">Table of n, a(n) for n = 0..15</a>
%F 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).
%t 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 *)
%o (Ruby)
%o def A(m, n)
%o a = Array.new(m, 1)
%o ary = [1]
%o while ary.size < n + 1
%o i = a[1..-1].inject(0){|s, i| s + i * i} + a[1..-1].inject(:*)
%o break if i % a[0] > 0
%o a = *a[1..-1], i / a[0]
%o ary << a[0]
%o end
%o ary
%o end
%o def A276126(n)
%o A(5, n)
%o end
%Y Cf. A165903, A276124.
%K nonn
%O 0,6
%A _Seiichi Manyama_, Aug 21 2016
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