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Squares-of-primes in which no two adjacent digits have the same parity.
2

%I #22 Jun 01 2022 01:56:36

%S 4,9,25,49,121,169,361,529,961,12769,16129,18769,32761,72361,76729,

%T 78961,96721,212521,214369,436921,452929,458329,1038361,1630729,

%U 1852321,3892729,5230369,5470921,5650129,5812921,5870929,7230721

%N Squares-of-primes in which no two adjacent digits have the same parity.

%C Intersection of A030141 and A001248. - _Michel Marcus_, Feb 06 2015

%H Giovanni Resta, <a href="/A030146/b030146.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A030145(n)^2. - _Giovanni Resta_, Aug 16 2018

%t Join[{4,9},Select[Prime[Range[4000]]^2,Union[Sort/@OddQ/@Partition[IntegerDigits[#],2,1]]=={{False,True}}&]] (* _Harvey P. Dale_, Feb 22 2011 *)

%Y Cf. A030145, A030152.

%K nonn,base

%O 1,1

%A _Patrick De Geest_

%E Definition clarified by _Harvey P. Dale_, Feb 23 2011

%E Offset changed by _Michel Marcus_, Feb 06 2015