A164932 Prime numbers in which the sum of the largest digit and the smallest digit is also a prime.

11, 23, 29, 41, 43, 47, 61, 67, 83, 89, 103, 107, 163, 211, 223, 229, 233, 239, 241, 269, 293, 307, 383, 421, 431, 433, 443, 449, 457, 461, 467, 479, 499, 503, 523, 547, 587, 607, 613, 631, 641, 647, 661, 677, 683, 701, 829, 853, 857, 863, 883, 929, 947

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

Cf. A000040, A164739

Sequence in context: A109981 A091367 A088136 * A086244 A091939 A072185

Adjacent sequences: A164929 A164930 A164931 * A164933 A164934 A164935

Keyword

base,nonn

Author

Parthasarathy Nambi, Aug 31 2009

Status

approved