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A345442
Denominators of irregular triangle of fractions arising from a problem of projecting into Hilbert space.
1
1, 2, 1, 4, 4, 8, 1, 16, 8, 8, 32, 16, 16, 1, 64, 32, 16, 16, 128, 64, 64, 32, 1, 256, 128, 32, 32, 64, 32, 512, 256, 256, 128, 128, 1, 1024, 512, 256, 16, 64, 128, 64, 2048, 1024, 1024, 512, 128, 256, 256, 1, 4096, 2048, 128, 512, 1024, 256, 128, 128, 8192, 4096, 4096, 2048, 2048, 512, 512, 512
OFFSET
1,2
LINKS
H. H. Bauschke and R. M. Corless, Analyzing a Projection Method with Maple, MapleTech Journal, 4:1 (1997), 2-7.
EXAMPLE
Triangle begins:
[0],
[1/2],
[0,1/4],
[1/4,1/8],
[0,3/16,1/8],
[1/8,3/32,1/16,1/16],
[0,7/64,5/32,1/16],
[1/16,7/128,5/64,7/64,1/32],
[0,15/256,17/128,3/32,1/32,1/64],
[1/32,15/512,17/256,29/256,9/128,3/128],
[0,31/1024,49/512,23/256,1/16,3/64,1/128],
...
PROG
(PARI) tabfd(nn) = my(m = htabl(nn), v = vector(nn, n, apply(denominator, Vec(m[n, ], len(m[n, ], n))))); for (n=1, #v, for (k=1, #v[n], print1(v[n][k], ", "))); \\ uses htabl and len from A345441 \\ Michel Marcus, Mar 20 2023
CROSSREFS
Cf. A345441 (numerators).
Sequence in context: A077967 A296188 A008312 * A060723 A300622 A195691
KEYWORD
nonn,frac,tabf
AUTHOR
N. J. A. Sloane, Jun 27 2021
EXTENSIONS
More terms from Michel Marcus, Mar 20 2023
STATUS
approved