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A108614 Semiprimes with non-semiprimes digits (no digits 4,6,9 in semiprimes). 1
10, 15, 21, 22, 25, 33, 35, 38, 51, 55, 57, 58, 77, 82, 85, 87, 111, 115, 118, 121, 122, 123, 133, 155, 158, 177, 178, 183, 185, 187, 201, 202, 203, 205, 213, 215, 217, 218, 221, 235, 237, 253, 278, 287, 301, 302, 303, 305, 321, 323, 327, 335, 355, 358, 371 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A107342 in the class of semiprimes.

This is to semiprimes A001358 as A034844 (Primes with nonprime digits) is to primes A000040. [Jonathan Vos Post, Jul 15 2010]

LINKS

Table of n, a(n) for n=1..55.

FORMULA

{j in A001358 and j not in A179463}. [Jonathan Vos Post, Jul 15 2010]

MATHEMATICA

cnd[n_]:=Plus@@Last/@FactorInteger[n]==2&&Union[FreeQ[IntegerDigits[n], # ]&/@{4, 6, 9}]=={True}; Select[Range[600], cnd[ # ]&]

CROSSREFS

Cf. A107342, A137167.

Cf. A107665, A107666, A111494, A111496, A111697, A179336. [Jonathan Vos Post, Jul 15 2010]

Sequence in context: A055986 A045161 A105156 * A336548 A115708 A068992

Adjacent sequences:  A108611 A108612 A108613 * A108615 A108616 A108617

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Jun 13 2005

STATUS

approved

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Last modified September 28 13:24 EDT 2020. Contains 337393 sequences. (Running on oeis4.)