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A158314 Consider a twin prime pair (p, q=p+2) such that the number of prime digits in p is equal to the number of odd digits in q; sequence lists values of p. 0

%I #25 May 18 2019 18:15:50

%S 3,5,59,281,347,521,599,659,821,857,1277,1427,2081,2381,2729,2801,

%T 3251,3359,3467,3539,3557,3767,3821,4127,4217,4229,4241,4271,4337,

%U 4421,4547,4637,4721,4787,4799,5021,5231,5477,5639,5657,5867,5879,6359,6659,6779

%N Consider a twin prime pair (p, q=p+2) such that the number of prime digits in p is equal to the number of odd digits in q; sequence lists values of p.

%t npdQ[{m_,n_}]:=Module[{r=Count[IntegerDigits[m],_?PrimeQ]},n-m==2&&r==Count[IntegerDigits[n],_?OddQ]]; Select[Partition[ Prime[ Range[ 1000]],2,1],npdQ][[All,1]] (* _Harvey P. Dale_, May 18 2019 *)

%Y Cf. A001359.

%K nonn,base,less

%O 1,1

%A _Juri-Stepan Gerasimov_, Mar 16 2009

%E Better definition from and data corrected (2381 to 3359 inserted) by _R. J. Mathar_, May 19 2010

%E Definition edited by _N. J. A. Sloane_, May 18 2019

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Last modified May 2 17:46 EDT 2024. Contains 372203 sequences. (Running on oeis4.)