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A111756 Greatest common divisors of consecutive terms of A091780. 0
3, 3, 3, 3, 5, 5, 5, 5, 5, 3, 7, 7, 7, 7, 5, 5, 9, 9, 3, 3, 11, 11, 11, 11, 5, 5, 13, 13, 13, 13, 3, 3, 17, 17, 17, 17, 5, 3, 19, 19, 19, 19, 5, 7, 7, 21, 3, 3, 23, 23, 23, 23, 5, 5, 3, 27, 3, 11, 7, 7, 13, 3, 29, 29, 29, 29, 5, 3, 31, 31, 31, 31, 5, 5, 3, 9, 3, 3, 37, 37, 37, 37, 5, 11, 11, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

It appears that each prime p>2 first appears in this sequence in a run of length 4, except for prime(3)=5, which first occurs in a run of length 5. This has been confirmed through prime(135)=761.

LINKS

Table of n, a(n) for n=0..85.

EXAMPLE

The fifth and sixth terms of A091780 are 15 and 10, respectively, so a(5)=5.

CROSSREFS

Cf. A091780.

Sequence in context: A162220 A118911 A190268 * A130821 A129756 A156724

Adjacent sequences:  A111753 A111754 A111755 * A111757 A111758 A111759

KEYWORD

nonn

AUTHOR

John W. Layman, Nov 21 2005

STATUS

approved

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Last modified December 10 14:27 EST 2019. Contains 329896 sequences. (Running on oeis4.)