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Numbers n where the largest and smallest decimal digit of prime(n) are both even.
1

%I #11 Oct 18 2018 11:56:04

%S 1,56,61,79,93,110,143,144,172,178,179,181,197,252,279,305,311,313,

%T 314,315,334,340,354,360,382,386,389,390,408,409,411,412,413,415,418,

%U 436,438,441,507,529,531,551,552,554,556,575,582,588,602,623,643,647,653

%N Numbers n where the largest and smallest decimal digit of prime(n) are both even.

%C Natural density 0.

%H Harvey P. Dale, <a href="/A154768/b154768.txt">Table of n, a(n) for n = 1..3000</a>

%t lseQ[n_]:=Module[{idp=IntegerDigits[Prime[n]]},AllTrue[{Max[ idp],Min[ idp]},EvenQ]]; Select[Range[1000],lseQ] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Oct 18 2018 *)

%K nonn,base,less

%O 1,2

%A _Juri-Stepan Gerasimov_, Jan 15 2009, May 13 2010

%E Corrected by _Harvey P. Dale_, Oct 18 2018