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A087913
Greatest number less than n such that the number of prime factors is one less than that of n; a(1)=0.
0
0, 1, 1, 3, 1, 5, 1, 6, 7, 7, 1, 10, 1, 13, 13, 12, 1, 15, 1, 15, 19, 19, 1, 20, 23, 23, 26, 26, 1, 26, 1, 24, 31, 31, 31, 30, 1, 37, 37, 30, 1, 39, 1, 39, 39, 43, 1, 40, 47, 49, 47, 51, 1, 52, 53, 52, 53, 53, 1, 52, 1, 61, 62, 48, 61, 65, 1, 65, 67, 69, 1, 60, 1, 73, 74, 74, 73
OFFSET
1,4
COMMENTS
A001222(a(n)) = A001222(n) - 1 for n>1.
CROSSREFS
Cf. A079890.
Sequence in context: A333976 A129510 A225656 * A090585 A309391 A147661
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 26 2003
STATUS
approved