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%I #19 Oct 15 2019 11:56:50
%S 2,11,13,17,19,23,29,37,41,43,47,59,61,67,71,73,79,83,89,101,103,107,
%T 109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,
%U 199,223,227,229,239,241,251,257,263,269,271,281,283,293,307,311,313
%N Primes expressible as the sum of an integer plus its digit sum.
%H Reinhard Zumkeller, <a href="/A048521/b048521.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a>
%F A107740(A049084(a(n))) > 0.
%e a(24) = prime 113 which is 106 + (1+0+6) (or 97 + (9+7)).
%t t={};Do[p=Prime[n];c=0;i=1;While[i<p&&c!=1,If[i+Total[IntegerDigits[i]] ==p,c=1;AppendTo[t,p]];i++],{n,65}];t (* _Jayanta Basu_, May 03 2013 *)
%t Union[Select[Table[n+Total[IntegerDigits[n]],{n,400}],PrimeQ]] (* _Harvey P. Dale_, Jul 14 2014 *)
%o (Haskell)
%o a048521 n = a048521_list !! (n-1)
%o a048521_list = map a000040 $ filter ((> 0) . a107740) [1..]
%o -- _Reinhard Zumkeller_, Sep 27 2014
%Y Cf. A007953, A047791, A048520.
%Y Cf. A006378, A062028, A107741.
%Y Cf. A000040, A107740, A049084.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, May 15 1999
%E Formula and also offset corrected by _Reinhard Zumkeller_, Sep 27 2014
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