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A271831
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Somos's sequence {a(6,n)} defined in comment in A018896: a(0)=a(1)= ... = a(13) = 1; for n>=14, a(n) = (a(n-1)*a(n-13) + a(n-7)^2)/a(n-14).
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8
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1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 12, 21, 37, 62, 98, 147, 358, 609, 959, 1541, 2618, 4655, 8407, 28631, 81011, 186528, 376741, 706041, 1280174, 3598503, 8411236, 24021605, 74880071, 219318499, 580374907, 1400227135, 6308924342
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OFFSET
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0,15
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LINKS
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MATHEMATICA
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a[n_ /; 0 <= n <= 14] = 1; a[n_]:= a[n] = (a[n-1]*a[n-13] + a[n-7]^2)/a[n -14]; Table[a[n], {n, 0, 50}] (* G. C. Greubel, Feb 21 2018 *)
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PROG
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(PARI) {a(n) = if(n<= 14, 1, (a(n-1)*a(n-13) + a(n-7)^2)/a(n-14))};
(Magma) [n le 14 select 1 else (Self(n-1)*Self(n-13) + Self(n-7)^2)/Self(n-14): n in [1..50]]; // G. C. Greubel, Feb 21 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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