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A154561 Primes resulting from (sum of digits of k) + (sum of digits of prime(k)) as k runs through the positive integers.

%I A154561 #9 Feb 11 2019 21:55:58
%S A154561 3,5,11,7,13,17,23,13,23,23,13,17,23,29,19,17,29,23,17,19,23,29,23,19,
%T A154561 31,23,17,19,29,31,31,23,11,19,19,17,19,23,17,17,17,23,29,31,23,29,23,
%U A154561 13,19,19,31,23,23,17,11,31,23,13,23,29,23,29,29,19,23,31,37,29,37,17
%N A154561 Primes resulting from (sum of digits of k) + (sum of digits of prime(k)) as k runs through the positive integers.
%e A154561 k=1 yields a term: prime(1) = 2 and 1 + 2 = 3 is prime, so a(1)=3;
%e A154561 k=2 yields a term: prime(2) = 3 and 2 + 3 = 5 is prime, so a(2)=5;
%e A154561 k=3 does not yield a term: prime(3) = 5 and 3 + 5 = 8 is composite;
%e A154561 k=4 yields a term: prime(4) = 7 and 4 + 7 = 11 is prime, so a(3)=11;
%e A154561 k=5 yields a term: prime(5) = 11 and 5 + 1 + 1 = 7 is prime, so a(4)=7.
%p A154561 A007953 := proc(n) add(d,d=convert(n,base,10)) ; end proc:
%p A154561 for n from 1 to 300 do a := A007953(n) +A007953(ithprime(n)) ; if isprime(a) then printf("%d,",a ) ; end if; end do: # _R. J. Mathar_, May 05 2010
%t A154561 sod[n_]:=Total[IntegerDigits[n]];Select[Table[sod[n]+sod[Prime[n]],{n,300}],PrimeQ] (* _Harvey P. Dale_, Dec 11 2012 *)
%Y A154561 Cf. A000040.
%K A154561 nonn,base
%O A154561 1,1
%A A154561 _Juri-Stepan Gerasimov_, Jan 12 2009
%E A154561 Corrected from a(35) onwards by _R. J. Mathar_, May 05 2010
%E A154561 Name corrected and Example section edited by _Jon E. Schoenfield_, Feb 11 2019