cp's OEIS Frontend

A271954 Somos's sequence {b(7,n)} defined in comment in A078495: a(0)=a(1)=...=a(16)=1; for n>=17, a(n)=(a(n-1)*a(n-16)+a(n-8)*a(n-9))/a(n-17).

%I A271954 #20 Sep 08 2022 08:46:16
%S A271954 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,3,4,5,6,7,8,9,11,17,29,49,79,121,
%T A271954 177,249,597,989,1483,2209,3425,5589,9447,16137,36240,109683,273382,
%U A271954 574885,1081260,1898415,3213378,5381793,15251949,31924773,78189885
%N A271954 Somos's sequence {b(7,n)} defined in comment in A078495: a(0)=a(1)=...=a(16)=1; for n>=17, a(n)=(a(n-1)*a(n-16)+a(n-8)*a(n-9))/a(n-17).
%H A271954 Seiichi Manyama, <a href="/A271954/b271954.txt">Table of n, a(n) for n = 0..487</a>
%t A271954 a[k_,n_]:=a[k,n]=If[n>2k+2,(a[k,(n-1)]*a[k,(n-2k-2)]+a[k,(n-k-1)]*a[k,(n-k-2)])/a[k,(n-2k-3)],1];
%t A271954 Map[a[7,#]&,Range[0,50]] (* _Peter J. C. Moses_, Apr 17 2016 *)
%o A271954 (PARI) {a(n) = if(n<= 17, 1, (a(n-1)*a(n-16) + a(n-8)*a(n-9))/a(n-17))}; for(n=1,50, print1(a(n), ", ")) \\ _G. C. Greubel_, Jul 30 2018
%o A271954 (Magma) [n le 17 select 1 else (Self(n-1)*Self(n-16)+Self(n-8)*Self(n-9))/Self(n-17): n in [1..60]]; // _G. C. Greubel_, Jul 30 2018
%Y A271954 Cf. A006721, A078495, A268199, A271948, A271949, A271950, A271952.
%K A271954 nonn
%O A271954 0,18
%A A271954 _Vladimir Shevelev_ and _Peter J. C. Moses_, Apr 17 2016