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A073902 Number of n-digit primes with digit sum n. 0

%I

%S 0,1,0,4,12,0,95,212,0,2395,10657,0,126068,375941,0,4943357,20513691,0

%N Number of n-digit primes with digit sum n.

%C a(3n)=0. - _Sascha Kurz_, Aug 23 2002

%e a(2) = 1 because the only two-digit prime with digit sum 2 is 11. a(5) = 12: the primes are 10103, 10211, 10301, 11003, 12011, 12101, 13001, 20021, 20201, 21011, 21101, and 30011.

%t Table[Length[Select[Prime[Range[PrimePi[10^(n-1)]+1,PrimePi[10^n]]], Total[IntegerDigits[#]]==n&]],{n,8}] (* _Harvey P. Dale_, Aug 09 2011 *)

%Y Cf. A069710.

%K base,nonn

%O 1,4

%A _Amarnath Murthy_, Aug 18 2002

%E More terms from _Sascha Kurz_, Aug 23 2002

%E a(4) and a(5) corrected, and example corrected, by _Harvey P. Dale_, Aug 09 2011

%E a(11) corrected and a(13)-a(15) from _Donovan Johnson_, Aug 10 2011

%E a(16)-a(18) from _David Radcliffe_, May 05 2015

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Last modified January 23 03:15 EST 2022. Contains 350504 sequences. (Running on oeis4.)