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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 (list; graph; refs; listen; history; text; internal format)
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

Amiram Eldar, Table of n, a(n) for n = 1..10000

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

Cf. A072587, A268335.

Similar sequences: A068140, A068781, A342188, A342189.

Sequence in context: A178755 A182261 A061757 * A088066 A116355 A071318

Adjacent sequences:  A342184 A342185 A342186 * A342188 A342189 A342190

KEYWORD

nonn

AUTHOR

Amiram Eldar, Mar 04 2021

STATUS

approved

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Last modified May 26 17:16 EDT 2022. Contains 354092 sequences. (Running on oeis4.)