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Zero-free primes with digit sum equal to 7.
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%I #7 Dec 04 2020 13:51:29

%S 7,43,61,151,223,241,313,331,421,1123,1213,1231,1321,2113,2131,2221,

%T 2311,3121,4111,11113,11131,11311,12211,21121,21211,22111,111121,

%U 111211,112111

%N Zero-free primes with digit sum equal to 7.

%C There are exactly 29 such primes the largest one being 112111.

%t Select[Prime[Range[11000]],DigitCount[#,10,0]==0&&Total[ IntegerDigits[ #]] == 7&] (* _Harvey P. Dale_, Dec 04 2020 *)

%o (PARI) isok(n) = isprime(n) && (sumdigits(n) == 7) && (vecmin(digits(n)) != 0); \\ _Michel Marcus_, Oct 10 2013

%Y Cf. A052221, A119461.

%K base,fini,full,nonn

%O 1,1

%A _Zak Seidov_, May 20 2006