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%I #19 Apr 18 2022 17:37:26
%S 17,173,179,317,617,1117,1171,1217,1709,1721,1723,1733,1741,1747,1753,
%T 1759,1777,1783,1787,1789,2017,2179,2417,2617,2917,3217,3517,3617,
%U 3917,4177,4217,4517,4817,5171,5179,5417,5717,6173,6217,6317,6917,7177,7417
%N Prime numbers containing the string 17.
%H Vincenzo Librandi, <a href="/A166579/b166579.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) ~ n log n. - _Charles R Greathouse IV_, Jun 20 2014
%p isA166579 := proc(n) local dgs,wrks; if isprime(n) then dgs := convert(n,base,10) ; wrks := false; for i from 1 to nops(dgs)-1 do if op(i,dgs) = 7 and op(i+1,dgs) = 1 then return true; end if; od: return false; else false; end if; end proc: for n from 1 to 8000 do if isA166579(n) then printf("%d,",n) ; end if; od: # _R. J. Mathar_, Nov 30 2009
%t p17Q[n_] := Module[{idn = IntegerDigits[n]}, MemberQ[Partition[idn, 2, 1], {1, 7}]]; Select[Prime[Range[1000]], p17Q] (* _Vincenzo Librandi_ Sep 14 2012 *)
%t Select[Prime[Range[1000]],SequenceCount[IntegerDigits[#],{1,7}]>0&] (* _Harvey P. Dale_, Apr 18 2022 *)
%o (PARI) contains(n,k)=my(N=digits(n),K=digits(k)); for(i=0,#N-#K, for(j=1,#K,if(N[i+j]!=K[j],next(2))); return(1)); 0
%o is(n)=isprime(n) && contains(n,17) \\ _Charles R Greathouse IV_, Jun 20 2014
%Y Cf. A166571 - A166573, A166580, A166581, A166582.
%K nonn,base,less
%O 1,1
%A _Vincenzo Librandi_, Nov 01 2009
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