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%I #22 Feb 04 2019 09:01:27
%S 1,15,16,17,18,19,44,45,46,47,48,116,117,118,119,245,246,290,291,292,
%T 293,294,374,375,376,425,426,427,428,429,431,432,433,434,435,436,437,
%U 438,439,441,486,487,488,489,527,528,529,580,581,582,627,628,629,684
%N Numbers k such that sum of digits of k = sum of digits of k-th positive nonprime.
%H Jinyuan Wang, <a href="/A176294/b176294.txt">Table of n, a(n) for n = 1..10000</a>
%e 15 is a term because the 15th positive nonprime in A018252 is 24, and 1 + 5 = 2 + 4 = 6. - _Bernard Schott_, Feb 04 2019
%p A007953 := proc(n) add(d,d=convert(n,base,10)) ; end proc:
%p A018252 := proc(n) option remember ; if n = 1 then 1; else for a from procname(n-1)+1 do if not isprime(a) then return a; end if; end do: end if; end proc:
%p for n from 1 to 900 do if A007953(n) = A007953(A018252(n)) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, Apr 20 2010
%o (PARI) k=0;for(n=1,684,k++;while(isprime(k),k++);if(sumdigits(n)==sumdigits(k),print1(n,", "))) \\ _Jinyuan Wang_, Feb 04 2019
%Y Cf. A018252.
%K nonn,base,less
%O 1,2
%A _Juri-Stepan Gerasimov_, Apr 14 2010
%E More terms from _R. J. Mathar_, Apr 20 2010
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