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 A074047 a(n)=a(n-1)*a(n-2)*a(n-3)*(1/a(n-1)+1/a(n-2)+1/a(n-3)) starting with a(1)=a(2)=a(3)=1. 2
 1, 1, 1, 3, 7, 31, 331, 12795, 4642051, 60935796571, 283646808320375611, 17285560913056915909539455163, 4902995236325455290013100337511909917402705547 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Using the simplified formula which extends the original one to terms that may be zero, one could prefix the values (1, 1, 0), cf. A121810. See also A203761 and references therein. - M. F. Hasler, Jan 01 2013 LINKS Table of n, a(n) for n=1..13. FORMULA a(n) tends towards a(n-1)^phi and 1.22376...^(phi^n) where phi=(1+sqrt(5))/2=1.6180339887... a(n)=a(n-1)*a(n-2)+a(n-3)*a(n-1)+a(n-2)*a(n-3). - M. F. Hasler, Jan 01 2013 EXAMPLE a(7)=31*7*3*(1/31+1/7+1/3)=331. MATHEMATICA RecurrenceTable[{a[n]==a[n-1]*a[n-2]+a[n-3]*a[n-1]+a[n-2]*a[n-3], a[1]==1, a[2]==1, a[3]==1}, a[n], {n, 1, 15}] (* Vaclav Kotesovec, Jan 20 2014 *) CROSSREFS Cf. A074046. Sequence in context: A063896 A277028 A156895 * A121810 A081475 A123212 Adjacent sequences: A074044 A074045 A074046 * A074048 A074049 A074050 KEYWORD nonn AUTHOR Henry Bottomley, Aug 14 2002 STATUS approved

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Last modified April 17 09:46 EDT 2024. Contains 371763 sequences. (Running on oeis4.)