A179463 - OEIS

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A179463

Semiprimes A001358 containing at least one semiprime digit in base 10.

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

Table of n, a(n) for n=1..58.

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 A372533 A374739

Adjacent sequences: A179460 A179461 A179462 * A179464 A179465 A179466

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