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A085125
Even numbers which are 7-smooth.
7
2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 24, 28, 30, 32, 36, 40, 42, 48, 50, 54, 56, 60, 64, 70, 72, 80, 84, 90, 96, 98, 100, 108, 112, 120, 126, 128, 140, 144, 150, 160, 162, 168, 180, 192, 196, 200, 210, 216, 224, 240, 250, 252, 256, 270, 280, 288, 294, 300, 320, 324, 336
OFFSET
1,1
COMMENTS
Equivalently, multiples of 2 with the largest prime divisor < 10.
FORMULA
From Amiram Eldar, Sep 23 2024: (Start)
a(n) = 2*A002473(n).
Sum_{n>=1} 1/a(n) = 35/16. (End)
MATHEMATICA
Select[2*Range[200], FactorInteger[#][[-1, 1]]<10&] (* Harvey P. Dale, Jul 06 2018 *)
CROSSREFS
Intersection of A005843 and A002473.
Sequence in context: A221284 A272670 A234521 * A251237 A194402 A134930
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, Jul 06 2003
EXTENSIONS
More terms from David Wasserman, Jan 28 2005
Offset changed by Andrew Howroyd, Sep 19 2024
STATUS
approved