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A321496 Numbers k such that k and k+1 have at least 6 but not both exactly 6 distinct prime factors. 6
58524465, 64822394, 130578734, 133595384, 143489709, 153124685, 155197965, 156532089, 157955720, 159653409, 165706904, 169075829, 170118234, 175458920, 184867605, 188377475, 193042394, 194236679, 195719810, 199150665, 202429590, 208727805, 209801514, 211588454 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Complement of A273879 (k and k+1 have exactly 6 distinct prime factors) in A321506 (k and k+1 have at least 6 distinct prime factors).

LINKS

Table of n, a(n) for n=1..24.

FORMULA

A321506 \ A273879.

MATHEMATICA

aQ[n_]:=Module[{v={PrimeNu[n], PrimeNu[n+1]}}, Min[v]>5 && v!={6, 6}]; Select[Range[10^9], aQ] (* Amiram Eldar, Nov 12 2018 *)

PROG

(PARI) is(n)=omega(n)>5&&omega(n+1)>5&&(omega(n)>6||omega(n+1)>6)

CROSSREFS

Cf. A273879, A321506; A321495 (analog for 5 factors).

Sequence in context: A172679 A034612 A015355 * A320211 A320220 A034644

Adjacent sequences:  A321493 A321494 A321495 * A321497 A321498 A321499

KEYWORD

nonn

AUTHOR

M. F. Hasler, Nov 12 2018

EXTENSIONS

More terms from Amiram Eldar, Nov 12 2018

STATUS

approved

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Last modified February 20 13:20 EST 2020. Contains 332077 sequences. (Running on oeis4.)