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A178045 Numbers of semiprimes between consecutive even numbers that are not semiprimes. 0
0, 2, 2, 2, 0, 0, 2, 2, 0, 0, 3, 2, 0, 0, 1, 1, 1, 0, 1, 2, 1, 1, 0, 1, 0, 1, 1, 0, 1, 3, 0, 1, 3, 0, 0, 0, 0, 1, 0, 1, 0, 1, 2, 3, 0, 0, 1, 0, 2, 0, 0, 3, 2, 0, 0, 0, 1, 2, 1, 0, 1, 1, 0, 0, 0, 2, 0, 1, 1, 1, 0, 0, 1, 0, 0, 3, 2, 1, 0, 3, 3, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 2, 0, 1, 1, 1, 1, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers of semiprimes between A176100(n) and A176100(n+1) where A176100 is twice the n-th nonprime numbers.

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

a(1)=0 because 2*A141468(1)=0<2=2*A141468(2); a(2)=2 because 2*A141468(2)=2<4(semiprime)<6(semiprime)<8=2*A141468(3).

CROSSREFS

Cf. A001358, A141468, A176851.

Sequence in context: A257921 A261119 A004541 * A321300 A037864 A285635

Adjacent sequences:  A178042 A178043 A178044 * A178046 A178047 A178048

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, May 18 2010

EXTENSIONS

a(66) and a(67) corrected by R. J. Mathar, May 28 2010

STATUS

approved

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Last modified January 23 23:56 EST 2021. Contains 340398 sequences. (Running on oeis4.)