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A151502 a(n) = A006720(n)^4 (fourth powers of Somos-4 sequence).

%I A151502 #28 Sep 08 2022 08:45:38
%S A151502 1,1,1,1,16,81,2401,279841,12117361,9721171216,5465500541281,
%T A151502 4541099550557761,48178257964790528961,148046697174216601867681,
%U A151502 3835980708567891638880403216,258045180612631702971803868544561,8100590302880631846481071607248577441
%N A151502 a(n) = A006720(n)^4 (fourth powers of Somos-4 sequence).
%H A151502 Seiichi Manyama, <a href="/A151502/b151502.txt">Table of n, a(n) for n = 0..76</a>
%F A151502 a(n) = A028945(n)^2 = A006720(n)^4. - _Seiichi Manyama_, Nov 20 2016
%t A151502 b[n_ /; 0 <= n <= 4] = 1; b[n_]:= b[n] = (b[n-1]*b[n-3] + b[n-2]^2)/b[n -4]; Table[(b[n])^4, {n, 0, 20}] (* _G. C. Greubel_, Sep 25 2018 *)
%o A151502 (PARI) {b(n) = if(n<4, 1, (b(n-1)*b(n-3) + b(n-2)^2)/b(n-4))};
%o A151502 for(n=0, 20, print1((b(n))^4, ", ")) \\ _G. C. Greubel_, Sep 25 2018
%o A151502 (PARI) b=vector(20); b[1]=b[2]=b[3]=1;b[4]=2; for(n=5, #b, b[n]=(b[n-1]*b[n-3]+b[n-2]^2)/b[n-4]); concat(1, vector(20, n, b[n]^4)) \\ _Altug Alkan_, Sep 25 2018
%o A151502 (Magma) I:=[1,1,1,1]; [n le 4 select I[n] else ((Self(n-1)*Self(n-3) + Self(n-2)^2)/Self(n-4))^4: n in [1..15]]; // _G. C. Greubel_, Sep 25 2018
%Y A151502 Cf. A006720(n)^k; A006720 (k=1), A028945 (k=2), A028935 (k=3), this sequence (k=4).
%K A151502 nonn
%O A151502 0,5
%A A151502 _N. J. A. Sloane_, May 14 2009