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A167631 Emirps A006567 with a sum of digits and a number of digits which are both primes. 0

%I

%S 113,157,179,199,311,337,359,733,739,751,937,953,971,991,10039,10079,

%T 10091,10253,10273,10321,10343,10453,10457,10459,10499,10613,10639,

%U 10651,10781,10853,10859,10891,10909,11003,11083,11159,11197,11243

%N Emirps A006567 with a sum of digits and a number of digits which are both primes.

%C Subsequence of A006567 and A028834. - _R. J. Mathar_, Nov 12 2009

%e 113 and 311 are distinct primes, and 3 (number of digits) and 5 (1+1+3) are also primes.

%o (PARI) sod(n)=my(s=0);while(n>9,s+=n%10;n\=10);s+n

%o R(n)=my(v=eval(Vec(Str(n))),s=0);forstep(i=#v,1,-1,s=10*s+v[i]);s

%o isA167631(n)=my(r); isprime(#Str(n)) && isprime(sod(n)) && isprime(n) && isprime(r=R(n)) && n!=r \\ _Charles R Greathouse IV_, Nov 10 2009

%K base,nonn

%O 1,1

%A _Claudio Meller_, Nov 07 2009

%E Edited by _Charles R Greathouse IV_ and _R. J. Mathar_, Nov 10 2009

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Last modified July 22 15:12 EDT 2019. Contains 325224 sequences. (Running on oeis4.)