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Primes expressible as the sum of a prime plus its digit sum.
14

%I #20 Sep 02 2023 16:39:50

%S 13,17,29,47,61,73,79,83,103,107,113,137,163,173,181,191,241,271,281,

%T 293,307,317,383,397,409,433,439,443,499,521,523,563,577,607,631,641,

%U 709,743,757,809,821,859,877,881,967,1019,1063,1069,1103,1163,1181

%N Primes expressible as the sum of a prime plus its digit sum.

%H M. F. Hasler, <a href="/A048520/b048520.txt">Table of n, a(n) for n = 1..10000</a>, Nov 08 2018

%e a(15) = 181 which is 167 + (1+6+7).

%t Sort[Select[Table[p=Prime[n];p+Total[IntegerDigits[p]],{n,195}],PrimeQ]] (* _Jayanta Basu_, May 03 2013 *)

%t Select[#+Total[IntegerDigits[#]]&/@Prime[Range[200]],PrimeQ]//Sort (* _Harvey P. Dale_, Sep 02 2023 *)

%o (PARI) is_A048520(n)=#select(p->p+sumdigits(p)==n,primes([n-9*#digits(n),n-2]))&&isprime(n) \\ _M. F. Hasler_, Nov 08 2018

%Y Cf. A007953, A047791, A048519.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, May 15 1999

%E Offset corrected to 1 by _M. F. Hasler_, Nov 08 2018