A028250 - OEIS

A028250

Sequence arising in multiprocessor page migration.

2, 5, 7, 10, 12, 15, 17, 20, 23, 25, 28, 30, 33, 35, 38, 40, 43, 46, 48, 51, 53, 56, 58, 61, 64, 66, 69, 71, 74, 76, 79, 81, 84, 87, 89, 92, 94, 97, 99, 102, 105, 107, 110, 112, 115, 117, 120, 122, 125, 128, 130, 133, 135, 138, 140, 143, 146, 148, 151, 153, 156, 158, 161, 163

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OFFSET

1,1

COMMENTS

a(n) minimizes the maximum of 1+(a(n)+1)/(2*n) and 1+(2*n+(a(n)+1)/2)/a(n). In case that a(n) is not unique and the same maximum occurs more than once, take the smaller value (assuming that this is a counter value on the nodes that is better if it stays small). - R. J. Mathar, Oct 26 2017

Is this the Beatty sequence b(n) = floor(k*n) with k = (sqrt(17)+1)/2? If not, and there is some n with a(n) != b(n), then a(n) = b(n) + 1 and n > 10^8. - Charles R Greathouse IV, Jan 27 2022

REFERENCES

J. Westbrook, Randomized algorithms for multiprocessor page migration, in "On-Line Algorithms", DIMACS Series in Discrete Math., Vol. 7, 1992, pp. 135-149.

LINKS

Table of n, a(n) for n=1..64.

J. Westbrook, Randomized algorithms for multiprocessor page migration, in "On-Line Algorithms", SIAM J. Comput., 23(5), 951-965. (15 pages), 1994, DOI

CROSSREFS

Sequence in context: A059536 A030193 A292653 * A190087 A182771 A109260

Adjacent sequences: A028247 A028248 A028249 * A028251 A028252 A028253

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

Terms beyond n=10 from R. J. Mathar, Oct 26 2017

STATUS

approved