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A342187
Numbers k such that both k and k+1 are not exponentially odd numbers.
3
44, 48, 49, 63, 75, 80, 98, 99, 116, 147, 171, 175, 207, 244, 260, 275, 288, 315, 324, 332, 360, 363, 368, 387, 404, 475, 476, 495, 507, 524, 528, 531, 539, 548, 549, 575, 603, 604, 624, 636, 656, 675, 692, 724, 725, 747, 764, 774, 800, 819, 832, 844, 845, 846
OFFSET
1,1
COMMENTS
The numbers of terms not exceeding 10^k for k = 2, 3, ..., are 8, 64, 624, 6281, 62779, 627904, 6279725, 62796307, 627961560, ... Apparently this sequence has an asymptotic density 0.062796...
LINKS
EXAMPLE
44 is a term since 44 = 2^2 * 11 and 45 = 3^2 * 5 both have an even exponent in their prime factorization.
MATHEMATICA
expOddQ[n_] := AllTrue[FactorInteger[n][[;; , 2]], OddQ]; Select[Range[10^3], !expOddQ[#] && !expOddQ[# + 1] &]
CROSSREFS
Similar sequences: A068140, A068781, A342188, A342189.
Sequence in context: A178755 A182261 A061757 * A365870 A088066 A116355
KEYWORD
nonn
AUTHOR
Amiram Eldar, Mar 04 2021
STATUS
approved