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A138372 Count of post-period decimal digits up to which the rounded n-th convergent to A103814 agrees with the exact value. 0
1, 3, 3, 4, 3, 4, 5, 6, 6, 7, 8, 8, 9, 10, 11, 12, 13, 13, 14, 16, 16, 18, 21, 23, 23, 24, 26, 27, 27, 29, 29, 30, 30, 31, 32, 34, 37, 36, 39, 40, 41, 42, 43, 43, 46, 47, 48, 48, 49, 50, 50, 52, 53, 54, 55, 56, 56, 58, 58, 59, 62, 63, 65, 66, 67, 68, 69, 70, 70, 71, 73, 73, 75 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

This is a measure of the quality of the n-th convergent to the Pentanacii constant

A103814 if the convergent and the exact value are compared rounded to an increasing

number of digits. The sequence of rounded values of A103814 is

2, 2.0, 1.97, 1.966, 1.9659, 1.96595, 1.965948, 1.9659482 etc. The n-th convergents

are 2 (n=1), 57/29 (n=2), 116/59 (n=3), 173/88 (n=4), 462/235 (n=5) etc, each with associated

rounded decimal expansions.

a(n) is the maximum number of post-period digits of the two expansions

if compared at the same level of rounding.

EXAMPLE

For n=5, the 5th convergent is 462/235 = 1.96595744.., with a sequence of rounded

representations 2, 2.0, 1.97, 1.966, 1.9660, 1.96596, etc.

Rounded to 1, 2, or 3 post-period decimal digits, this is the same as the rounded version

of the exact value, but disagrees if both are rounded to 4 decimal digits, where 1.9659 <> 1.9660.

So a(n=5)= 3 (digits), the maximum rounding level with agreement.

CROSSREFS

Cf. A138335 - A138339, A138343, A138366, A138367, A138369 - A138371, A138373 - A138374.

Sequence in context: A096139 A175928 A161357 * A123708 A102302 A130896

Adjacent sequences:  A138369 A138370 A138371 * A138373 A138374 A138375

KEYWORD

base,nonn

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Mar 17 2008

EXTENSIONS

Definition and values replaced as defined via continued fractions - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 01 2009

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Last modified February 15 15:20 EST 2012. Contains 205823 sequences.