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A372099
Exponents k where A000120(3^k) - A070939(3^k)/2 reaches a new maximum.
4
0, 1, 3, 5, 11, 27, 71, 119, 140, 158, 198, 218, 441, 537, 538, 868, 1092, 2128, 2294, 2343, 2811, 2911, 3849, 4003, 4655, 5079, 5279, 5920, 6269, 6603, 10181, 10574, 12801, 12803, 15563, 15784, 16054, 16253, 17127, 18257, 20187, 21934, 34633, 49209, 76791, 78938
OFFSET
1,3
COMMENTS
These are the k-values ​​of the upper envelope of the scatter band of the deviation of the binary weight of 3^k from half the length of the corresponding binary number. The corresponding differences are given in A372100.
LINKS
Hugo Pfoertner, Illustration of scatter band bounded by lower and upper records, up to exponents k=8.5*10^6.
PROG
(PARI) a372099(upto) = {my(dm=oo); for (k=0, upto, my (p=3^k, h=hammingweight(p), b=#binary(p)/2, d=b-h); if (d<dm, print1(k, ", "); dm=d))};
a372099(80000)
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Apr 25 2024
STATUS
approved