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%I #17 Jun 23 2015 08:01:38
%S 1,2,7,20,28,58,95,154,226,278,403,570,734,949,1200,1515,1931,2328,
%T 2908,3529,4196,5034,5800,6870,7871,9132,10574,12359,14005,15871,
%U 17924,20231,22505,25903,28800,31532,34830,38479,43334,48847,52769,57173,61545,67774,75186
%N Number of n-digit primes whose sum of digits is 7.
%H Giovanni Resta, <a href="/A259144/b259144.txt">Table of n, a(n) for n = 1..100</a>
%o (PARI) a(n)=n--; my(A,B,C,D); sum(a=0,n, A=10^n+10^a+1; sum(b=a,n, B=A+10^b; sum(c=b,n, C=B+10^c; sum(d=c,n, D=C+10^d; sum(e=d,n, isprime(D+10^e)))))) \\ _Charles R Greathouse IV_, Jun 19 2015
%Y Cf. A007953, A052221, A062337.
%K nonn,base
%O 1,2
%A _Zak Seidov_, Jun 19 2015
%E More terms from _Alois P. Heinz_, Jun 19 2015
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