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A072049
a(n) = floor(2^(n/(floor(n*log(2)/log(prime(n)))))).
1
2, 4, 8, 16, 32, 64, 128, 256, 512, 32, 45, 64, 90, 128, 181, 256, 362, 64, 80, 101, 128, 161, 203, 256, 322, 406, 107, 128, 152, 181, 215, 256, 304, 362, 430, 512, 168, 194, 222, 256, 294, 337, 388, 445, 512, 203, 228, 256, 287, 322, 362, 406, 456, 512, 574
OFFSET
1,1
COMMENTS
The sequence comes from the relationship of the primes to powers of two: in Sierpiński gasket sets the number s(n)=log(prime(n))/log(2) is the Moran dimension of unique fractal types. I first thought of making numbers that take these to integers by multiplication. And then of using integers of those to make other integers as powers of two that were prime like.
The sequence is slow to increase and has an alternating effect so that it dips lower after reaching a peak.
MATHEMATICA
Table[Floor[2^(n/(Floor[n * Log[2]/Log[Prime[n]]]))], {n, 60}]
CROSSREFS
Sequence in context: A101440 A126605 A072067 * A281938 A242350 A115213
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Jul 30 2002
EXTENSIONS
Edited by Robert G. Wilson v, Jul 31 2002
STATUS
approved