OFFSET
1,1
COMMENTS
If there is more than one digit with the same value (like in 211) only one is counted.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
The sum of the largest digit and the smallest digit in the prime 947 is also a prime.
MATHEMATICA
sldsdQ[n_]:=Module[{idn=IntegerDigits[n]}, PrimeQ[Min[idn]+Max[idn]]]; Select[Prime[Range[200]], sldsdQ] (* Harvey P. Dale, Jul 17 2018 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Parthasarathy Nambi, Aug 31 2009
STATUS
approved