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Intersection of A000028 and A028260.
3

%I #12 Nov 30 2024 12:58:36

%S 4,9,16,24,25,40,49,54,56,60,81,84,88,90,96,104,121,126,132,135,136,

%T 140,150,152,156,160,169,184,189,198,204,220,224,228,232,234,240,248,

%U 250,256,260,276,289,294,296,297,306,308,315,328,336,340,342,344,348,350

%N Intersection of A000028 and A028260.

%C First differs from A066427 at n = 11, where A066427(11) = 72 is missing from this sequence.

%H Paolo Xausa, <a href="/A378489/b378489.txt">Table of n, a(n) for n = 1..10000</a>

%t A000028Q[k_] := k > 1 && OddQ[Count[IntegerDigits[FactorInteger[k][[All, 2]], 2], 1, 2]];

%t A028260Q[k_] := EvenQ[PrimeOmega[k]];

%t Select[Range[500], A000028Q[#] && A028260Q[#] &]

%Y Cf. A000028, A028260, A066427, A378494.

%K nonn

%O 1,1

%A _Paolo Xausa_, Nov 28 2024, following a suggestion from _Peter Munn_.