cp's OEIS Frontend

A271628 Primes that are the sum of the digits of the numbers from 1 to n, for some n.

%I A271628 #13 Apr 11 2016 23:26:29
%S A271628 3,73,109,127,433,1009,1117,1801,2017,2089,2143,2467,2503,2791,3079,
%T A271628 3331,3583,4159,4519,4663,4951,5437,5581,5923,6121,6301,6553,7039,
%U A271628 7561,8353,8623,8821,9001,9199,9631,9811,10837,11719,12637,13177,13249,13627,14401,15391
%N A271628 Primes that are the sum of the digits of the numbers from 1 to n, for some n.
%H A271628 Paolo P. Lava, <a href="/A271628/b271628.txt">Table of n, a(n) for n = 1..10000</a>
%e A271628 The sum of the digits of 1 and 2 is a prime: 1 + 2 = 3.
%e A271628 The sum of the digits of the number from 1 to 16 is a prime: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 1 + 0 + 1 + 1 + 1 + 2 + 1 + 3 + 1 + 4 + 1 + 5 + 1 + 6 = 73.
%p A271628 with(numtheory): P:=proc(q) local a,b,c,k,n; a:=0;
%p A271628 for n from 0 to q do b:=0; c:=n; for k from 1 to ilog10(n)+1 do b:=b+(c mod 10); c:=trunc(c/10); od; a:=a+b;
%p A271628 if isprime(a) then print(a); fi; od; end: P(10^6);
%t A271628 Select[Accumulate@ Map[Total@ IntegerDigits@ # &, Range[0, 1200]], PrimeQ] (* _Michael De Vlieger_, Apr 11 2016 *)
%o A271628 (PARI) lista(nn) = for (n=1, nn, if (isprime(p=sum(k=1, n, sumdigits(k))), print1(p, ", "))); \\ _Michel Marcus_, Apr 11 2016
%Y A271628 Cf. A000040, A037123, A271626.
%K A271628 nonn,easy,base
%O A271628 1,1
%A A271628 _Paolo P. Lava_, Apr 11 2016