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A166582
Primes containing the string 444.
13
4441, 4447, 14447, 14449, 24443, 44417, 44449, 44453, 44483, 44491, 44497, 54443, 54449, 74441, 74449, 84443, 84449, 94441, 94447, 124447, 134443, 144407, 144409, 144413, 144427, 144439, 144451, 144461, 144479, 144481, 144497, 164443, 164447
OFFSET
1,1
LINKS
FORMULA
a(n) ~ n log n. - Charles R Greathouse IV, Nov 01 2022
MATHEMATICA
p444Q[n_] := Module[{idn = IntegerDigits[n]}, MemberQ[Partition[idn, 3, 1], {4, 4, 4}]]; Select[Prime[Range[20000]], p444Q] (* Vincenzo Librandi Sep 14 2012 *)
Select[Prime[Range[16000]], SequenceCount[IntegerDigits[#], {4, 4, 4}]>0&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 15 2018 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vincenzo Librandi, Nov 01 2009
EXTENSIONS
Corrected (144491 replaced by 144497) by R. J. Mathar, Nov 30 2009
STATUS
approved