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A095678 Minimal sequence such that all triples of consecutive numbers have no common divisor greater than 1, but all three pairs within the triples are not coprime. 0
6, 10, 15, 12, 20, 45, 18, 40, 75, 24, 50, 135, 36, 80, 225, 48, 100, 375, 54, 160, 405, 72, 200, 675, 96, 250, 1125, 108, 320, 1215, 144, 400, 1875, 162, 500, 2025, 192, 640, 3375, 216, 800, 3645, 288, 1000, 5625, 324, 1250, 6075, 384, 1280, 9375, 432 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

GCD(a(n),a(n+1),a(n+2)) = 1, GCD(a(n),a(n+1)) > 1, GCD(a(n),a(n+2)) > 1 and GCD(a(n+1),a(n+2)) > 1;

A001221(a(n)) = 2; 2 <= A020639(a(n)) <= 3 <= A006530(a(n)) <= 5.

LINKS

Table of n, a(n) for n=1..52.

CROSSREFS

Sequence in context: A171251 A074980 A059218 * A151972 A094564 A271354

Adjacent sequences:  A095675 A095676 A095677 * A095679 A095680 A095681

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 04 2004

STATUS

approved

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Last modified May 21 01:26 EDT 2019. Contains 323429 sequences. (Running on oeis4.)