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A230255 Emirps whose sum of digits is prime. 1

%I

%S 113,157,179,199,311,337,359,733,739,751,937,953,971,991,1031,1033,

%T 1091,1097,1103,1109,1181,1213,1217,1231,1237,1259,1279,1301,1321,

%U 1381,1439,1453,1471,1499,1523,1583,1619,1657,1723,1741,1811,1831,1901,1949,3011,3019

%N Emirps whose sum of digits is prime.

%H K. D. Bajpai, <a href="/A230255/b230255.txt">Table of n, a(n) for n = 1..8500</a>

%e a(6)= 337 is emirp. Sum of digits= 3+3+7= 13 which is prime.

%e a(11)= 937 is emirp. Sum of digits= 9+3+7= 19 which is prime.

%p with(StringTools):KD:= proc() local a,b,d; a:=ithprime(n);b:=parse(Reverse(convert(a,string))); d:=add( i,i = convert((a), base, 10))(a);if a<>b and isprime(b) and isprime(d) then return(a):fi; end: seq(KD(),n=1..2000);

%Y Cf. A006567 (emirps: primes whose reversal is different prime).

%Y Cf. A082806 (palindromic primes: sum of digits is prime).

%Y Cf. A178092 (emirps: digital sum is emirp).

%K nonn,base,less

%O 1,1

%A _K. D. Bajpai_, Oct 14 2013

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Last modified August 10 12:39 EDT 2020. Contains 336379 sequences. (Running on oeis4.)