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%I #16 Aug 19 2021 06:41:31
%S 2,3,5,7,101,131,151,181,191,313,353,373,383,727,757,787,797,919,929,
%T 10301,10501,10601,12421,12721,12821,13831,13931,14341,14741,15451,
%U 16061,16361,16561,17471,17971,18181,18481,19391,19891,30103,30203
%N Palindromic primes containing no pair of consecutive equal digits.
%H Robert Israel, <a href="/A050784/b050784.txt">Table of n, a(n) for n = 1..10000</a>
%p nextL:= proc(L) local V,j,n,k;
%p n:= LinearAlgebra:-Dimension(L);
%p V:= L;
%p for j from n to 1 by -1 do
%p V[j]:= V[j]+1;
%p if j > 1 then if V[j] = V[j-1] then V[j]:= V[j]+1 fi
%p elif member(V[j],[2,8]) then V[j]:= V[j]+1
%p elif member(V[j],[4,5,6]) then V[j]:= 7
%p fi;
%p if V[j] <= 9 then
%p for k from j+1 to n do if (k-j)::odd then V[k]:= 0 else V[k]:= 1 fi od;
%p return V
%p fi;
%p od;
%p Vector(n+1, i -> i mod 2)
%p end proc:
%p Pali:= proc(L)
%p local i,n;
%p n:= LinearAlgebra:-Dimension(L);
%p add(L[i]*10^(2*n-i-1),i=1..n)+add(L[i]*10^(i-1),i=1..n-1)
%p end proc:
%p V:= <5>: Res:= 2,3,5: count:= 3:
%p while count < 100 do
%p V:= nextL(V);
%p x:= Pali(V);
%p if isprime(x) then count:= count+1; Res:= Res, x fi;
%p od:
%p Res; # _Robert Israel_, Feb 07 2019
%t Select[Prime[Range[3280]],Reverse[x=IntegerDigits[#]]==x&&FreeQ[Differences[x],0]&] (* _Jayanta Basu_, Jun 01 2013 *)
%Y Cf. A002385, A050783, A030147, A050757, A046075.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Sep 15 1999
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