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A086007 Number of semiprime triples <= n. 0
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,85

COMMENTS

A semiprime triple is <= n if its least member is <= n;

if a(n-1)<a(n) then (n,n+1,n+2) is a semiprime triple, A086005(a(n))=n+1.

LINKS

Table of n, a(n) for n=1..102.

CROSSREFS

Cf. A001358, A086005.

Sequence in context: A209253 A165113 A069903 * A108582 A071840 A000193

Adjacent sequences:  A086004 A086005 A086006 * A086008 A086009 A086010

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jul 07 2003

STATUS

approved

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Last modified June 27 19:44 EDT 2017. Contains 288790 sequences.