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%I #11 Jul 30 2019 15:33:51
%S 2,3,5,7,11,13,19,23,31,113,127,137,181,269,277,281,311,461,463,661,
%T 673,677,1019,1277,1361,1973,2287,2339,2377,2411,2423,2689,2731,4673,
%U 5023,5081,5261,6563,6577,8311,9013,9437,9439,10181,10463
%N Primes such that in p^2 the parity of digits alternates.
%H Giovanni Resta, <a href="/A030145/b030145.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n)^2 = A030146(n). - _Giovanni Resta_, Aug 16 2018
%t id[n_]:=IntegerDigits[n]; t={}; Do[p=Prime[n]; If[Length[id[p]]==1,AppendTo[t,p], If[Union[Abs[Differences[Boole/@EvenQ[id[p^2]]]]]=={1}, AppendTo[t,p]]], {n,1300}]; t (* _Jayanta Basu_, May 07 2013 *)
%t pdaQ[n_]:=FreeQ[Differences[Boole[EvenQ[IntegerDigits[n^2]]]],0]; Select[ Prime[ Range[1300]],pdaQ] (* _Harvey P. Dale_, Jul 30 2019 *)
%Y Cf. A030144, A030146, A030151.
%K nonn,base
%O 1,1
%A _Patrick De Geest_
%E Offset corrected by _Giovanni Resta_, Aug 16 2018
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