|
%I #14 May 29 2013 16:50:01
%S 1,2,3,4,5,9,10,13,14,15,18,19,23,24,26,30,32,33,34,36,37,40,41,43,44,
%T 45,46,48,49,50,53,56,57,60,61,64,65,66,67,68,71,72,74,75,78,79,80,82,
%U 86,87,89,90,91,93,102,105,106,108,109,110,111,116,117,118,121,124,128
%N Indices of additive primes - primes with prime sum-of-digits, see A046704.
%C There are 107 additive primes among first 200 primes. There are 38455 additive primes among first 100000 primes. Additive primes are in A046704.
%H Zak Seidov, <a href="/A075177/b075177.txt">Table of n, a(n) for n=1..4086, a(n)<10^4.</a>
%F PrimePi[A046704(n)]
%F A000040(a(n)) = A046704(n).
%e Prime(10)=29 is additive prime because 2+9=11 is prime.
%t Map[PrimePi[ # ]&, Select[Prime[Range[200]], PrimeQ[Apply[ Plus, IntegerDigits[ # ]]]&]
%t Flatten[Position[Prime[Range[150]],_?(PrimeQ[Total[IntegerDigits[#]]]&),{1},Heads->False]] (* _Harvey P. Dale_, May 29 2013 *)
%o (Haskell)
%o import Data.List (elemIndices)
%o a075177 n = a075177_list !! (n-1)
%o a075177_list = map (+ 1) $
%o elemIndices 1 $ map (a010051 . a007953) a000040_list
%o -- _Reinhard Zumkeller_, Nov 13 2011
%Y Cf. A046704.
%Y Cf. A007953, A010051.
%K nonn,base
%O 1,2
%A _Zak Seidov_, Sep 06 2002
|
