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A179463 Semiprimes A001358 containing at least one semiprime digit in base 10. 1
4, 6, 9, 14, 26, 34, 39, 46, 49, 62, 65, 69, 74, 86, 91, 93, 94, 95, 106, 119, 129, 134, 141, 142, 143, 145, 146, 159, 161, 166, 169, 194, 206, 209, 214, 219, 226, 247, 249, 254, 259, 262, 265, 267, 274, 289, 291, 295, 298, 299, 309, 314, 319, 326, 329, 334, 339, 341 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Semiprimes containing at least one 4, 6, or 9 digit base 10.
This is to semiprimes A001358 as A179336 is to primes A000040.
This properly includes the subset A107342 Semiprimes with semiprime digits.
LINKS
MATHEMATICA
spdQ[n_]:=Module[{idn=IntegerDigits[n]}, MemberQ[idn, 4] || MemberQ[ idn, 6] || MemberQ[ idn, 9]]; Select[Select[Range[350], PrimeOmega[#]==2&], spdQ] (* Harvey P. Dale, Jun 24 2013 *)
CROSSREFS
Cf. A107342 Semiprimes with semiprime digits (digits 4, 6, 9 only), A107665 Numbers with semiprime digits (digits 4, 6, 9 only), A107666 Primes with semiprime digits (digits 4, 6, 9 only), A111494, A111496, A111697, A108614 Semiprimes with non-semiprimes digits (no digits 4, 6, 9 in semiprimes), A179336.
Sequence in context: A020706 A226271 A137371 * A086697 A287568 A251728
KEYWORD
base,easy,nonn,less
AUTHOR
Jonathan Vos Post, Jul 15 2010
EXTENSIONS
Corrected (a(37) added) by Harvey P. Dale, Jun 24 2013
STATUS
approved

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Last modified March 28 11:59 EDT 2024. Contains 371254 sequences. (Running on oeis4.)