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 A141522 a(1) = 0, a(2) = a(3) = 1; a(n) = a(n-1)*a(n-2) + a(n-1)*a(n-3) for n > 3. 1
 0, 1, 1, 1, 2, 4, 12, 72, 1152, 96768, 118444032, 11598039613440, 1374840894208868352000, 15945621994910596019667697926144000, 21922693387137438627357958684974264478793362424463360000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 REFERENCES Martin Gardner, Mathematical Circus, Random House, New York, 1981, p. 165. LINKS Michael De Vlieger, Table of n, a(n) for n = 1..21 MATHEMATICA Nest[Append[#, #[[-1]] #[[-2]] + #[[-1]] #[[-3]]] &, {0, 1, 1}, 12] (* Michael De Vlieger, Dec 17 2017 *) PROG (MATLAB) function y=fib(n) %Generates running geometric numbers( second kind) fz(1)=0; fz(2)=1; fz(3)=1; for k=4:n fz(k)=fz(k-1)*(fz(k-2)+fz(k-3)); end y=fz(n); (PARI) /* script that avoids arrays */ geom(n) = { local(a=0, b=1, c=1, d); print1(a", "b", "c", "); for(x=1, n-3, d=(a+b)*c; print1(d", "); a=b; b=c; c=d; ) } \\ Cino Hilliard, Apr 29 2009 CROSSREFS Sequence in context: A078919 A085864 A060935 * A114903 A038054 A003180 Adjacent sequences:  A141519 A141520 A141521 * A141523 A141524 A141525 KEYWORD nonn AUTHOR Matt Wynne (matwyn(AT)verizon.net), Aug 11 2008 STATUS approved

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Last modified April 3 21:54 EDT 2020. Contains 333207 sequences. (Running on oeis4.)