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A081329 Numbers having no representation as sum of two 3-smooth numbers. 5
1, 23, 46, 47, 53, 61, 69, 71, 77, 79, 92, 94, 95, 101, 103, 106, 107, 115, 119, 121, 122, 125, 127, 133, 138, 139, 141, 142, 143, 149, 151, 154, 157, 158, 159, 161, 167, 169, 173, 175, 179, 181, 183, 184, 185, 187, 188, 190, 191, 197, 199, 202, 203, 205, 206 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A081326(a(n))=0; complement of A081330.

EXAMPLE

For all 3-smooth numbers m<23 the greatest prime factor of 23-m is >3: 23-1=2*11, 23-2=3*7, 23-3=4*5, 23-2^2=19, 23-2*3=17, 23-2^3=3*5, 23-3^2=2*7, 23-3*2^2=11, 23-2^4=7, 23-2*3^2=5, therefore 23 is a term.

CROSSREFS

Cf. A003586.

Sequence in context: A030656 A122041 A040506 * A025022 A094694 A164010

Adjacent sequences:  A081326 A081327 A081328 * A081330 A081331 A081332

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Mar 19 2003

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Last modified February 16 16:00 EST 2012. Contains 205938 sequences.