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A364405
Numbers k such that k is never the smallest number which requires the maximum number of steps for the Euclidean algorithm for computing gcd(k,m) for any m > k.
1
12, 16, 20, 24, 38, 46, 48, 50, 54, 56, 66, 70, 78, 81, 84, 88, 91, 96, 98, 99, 100, 104, 116, 122, 126, 130, 132, 135, 138, 141, 148, 150, 155, 156, 161, 162, 164, 166, 168, 176, 180, 182, 193, 196, 200, 201, 204, 205, 210, 212, 214, 218, 220, 228, 232, 234, 236
OFFSET
1,1
COMMENTS
Positive numbers not in A084242.
PROG
(Ruby)
def gcdsteps(k, m)
k.zero? ? 0 : 1 + gcdsteps(m % k, k)
end
flags = [nil, *1..2000]
(1..flags.length).each do |m|
scores = []
(1..m).each do |k|
scores << [gcdsteps(k, m), k]
end
flags[scores.sort_by { |n| -n[0] }.first[1]] = nil
end
puts flags[1..flags.length / 2].compact
CROSSREFS
Sequence in context: A225071 A210577 A231903 * A337703 A337700 A243538
KEYWORD
nonn
AUTHOR
John Metcalf, Jul 22 2023
STATUS
approved