A030475 - OEIS

%I #12 Oct 18 2023 11:52:39

%S 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,

%T 97,113,131,137,139,151,157,173,179,191,193,197,199,211,223,227,229,

%U 233,239,241,251,257,263,269,271,277,281,283,293,311,313,317

%N Primes with property that all even digits occur together and all odd digits occur together.

%H Robert Israel, <a href="/A030475/b030475.txt">Table of n, a(n) for n = 1..10000</a>

%p filter:= proc(n) local L; L:= convert(n,base,10) mod 2;

%p   not member(-1,L[1..-2]-L[2..-1])

%p end proc:

%p select(filter, [seq(ithprime(i),i=1..1000)]);

%t With[{upto=100},Select[Prime[Range[upto]],Length[SplitBy[IntegerDigits[#],Mod[#,2]&]]<3&]] (* _Paolo Xausa_, Oct 18 2023 *)

%Y Cf. A030476, A030480.

%K nonn,base

%O 1,1

%A _Patrick De Geest_

%E Offset changed by _Robert Israel_, Oct 17 2023