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A115043 a(0)=3, a(1)=5. a(n) = a(n-1)*a(n-2) if n odd, else a(n) = a(n-1)/a(n-2). 1
3, 5, 15, 3, 45, 15, 675, 45, 30375, 675, 20503125, 30375, 622782421875, 20503125, 12768985843505859375, 622782421875, 7952299928506168842315673828125, 12768985843505859375 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

All divisors >1 of the terms are also in the sequence.

LINKS

Table of n, a(n) for n=0..17.

FORMULA

a(n) = a(n-2)*a(n-4) if n odd. a(n)=a(n-3) if n even.

a(2n+1) = 3^Fibonacci(n+1) * 5^Fibonacci(n).

a(2n) = 3^Fibonacci(n-1) * 5^Fibonacci(n-2).

CROSSREFS

Cf. A115033, A115034, A174348.

Sequence in context: A273164 A317661 A339972 * A272255 A270688 A270453

Adjacent sequences:  A115040 A115041 A115042 * A115044 A115045 A115046

KEYWORD

easy,nonn

AUTHOR

Giovanni Teofilatto, Feb 28 2006

EXTENSIONS

Formulas corrected by R. J. Mathar, Mar 16 2010

STATUS

approved

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Last modified July 25 12:15 EDT 2021. Contains 346290 sequences. (Running on oeis4.)