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A253106
Semiprimes with smallest factor <= 3.
3
4, 6, 9, 10, 14, 15, 21, 22, 26, 33, 34, 38, 39, 46, 51, 57, 58, 62, 69, 74, 82, 86, 87, 93, 94, 106, 111, 118, 122, 123, 129, 134, 141, 142, 146, 158, 159, 166, 177, 178, 183, 194, 201, 202, 206, 213, 214, 218, 219, 226, 237, 249, 254, 262, 267, 274, 278
OFFSET
1,1
COMMENTS
A253046(a(n)) != a(n).
LINKS
PROG
(Haskell)
a253106 n = a253106_list !! (n-1)
a253106_list = filter f [1..] where
f x = p <= 3 && a010051' (div x p) == 1 where p = a020639 x
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Dec 26 2014
STATUS
approved