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A137722 Number of numbers not greater than n with exactly one prime gap in their factorization. 3
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 4, 5, 5, 5, 5, 6, 6, 7, 7, 7, 7, 7, 8, 9, 9, 9, 9, 10, 11, 12, 12, 13, 13, 14, 14, 15, 15, 15, 15, 16, 17, 18, 18, 18, 19, 20, 21, 22, 22, 22, 22, 23, 24, 24, 25, 26, 26, 27, 28, 29, 29, 29, 29, 30, 30, 31, 31, 32, 32, 33, 33, 34 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,14

COMMENTS

a(n) > a(n-1) iff A073490(n) = 1;

A137721(n) > a(n) for n < 134;

A137721(n) < a(n) for n > 140.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..1000

CROSSREFS

Cf. A073493.

Sequence in context: A103374 A208251 A241087 * A081305 A035665 A027388

Adjacent sequences:  A137719 A137720 A137721 * A137723 A137724 A137725

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Feb 09 2008

STATUS

approved

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Last modified October 21 09:39 EDT 2014. Contains 248377 sequences.