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A081304
Number of numbers m <= n with prime factors less than 2*spf(m), where spf(m) is the smallest prime factor of m (A020639).
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 9, 10, 11, 12, 12, 13, 14, 15, 16, 17, 17, 17, 17, 18, 19, 20, 20, 21, 21, 22, 22, 23, 24, 24, 24, 25, 26, 27, 27, 27, 27, 28, 28, 29, 29, 30, 30, 31, 32, 33, 33, 33, 33, 34, 35, 35, 35, 35, 35, 36, 36, 37, 37, 37, 38, 38, 38, 39, 39, 39, 39, 40, 41, 42
OFFSET
1,2
COMMENTS
a(n)+A081305(n)=n; a(114)=A081305(114)=57;
a(n)>=n/2 for n<=114, a(n)<n/2 for n>114.
CROSSREFS
Sequence in context: A353024 A100637 A081063 * A137721 A245339 A324161
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Mar 17 2003
STATUS
approved