A257342 Solution to Popular Computing Problem 56 (decimal).

8, 8, 9, 0, 0, 0, 3, 5, 4, 9, 6, 9, 5, 2, 3, 0, 1, 3, 9, 3, 4, 6, 7, 1, 9, 6, 9, 0, 8, 7, 9, 1, 2, 9, 3, 1, 0, 5, 3, 8, 4, 8, 0, 2, 1, 0, 1, 7, 9, 5, 4, 3, 4, 1, 4, 5, 4, 3, 4, 6, 5, 3, 7, 0, 0, 3, 2, 3, 9, 6, 3, 5, 0, 8, 5, 2, 5, 3, 1, 2, 8, 6, 1, 1, 0, 9, 8

Offset

0,1

Comments

See link for precise definition. This is the constant in A257341 written in base 10.

Links

Chai Wah Wu, Table of n, a(n) for n = 0..10000

Popular Computing (Calabasas, CA), Solution to Problem 56, Vol. 4 (No. 39, June 1976), page PC39-3 [Annotated and scanned copy]

Example

0.88900035496952301393467196908791293...

Prog

(Python)
from fractions import Fraction
from math import log10
A257342_list, m, y = [], 2, Fraction(0, 1)
for i in range(2, 100):
    for j in range(1, i):
        x = Fraction(j, i)
        if x.denominator == i:
            y += Fraction(int(m*x) % 2, m)
            m *= 2
for i in range(int(log10(m))-2):
    y *= 10
    A257342_list.append(int(y) % 10) # Chai Wah Wu, Apr 29 2015

Crossrefs

Cf. A020652, A038567, A257341.

Sequence in context: A266209 A077106 A255287 * A252850 A316163 A346908

Adjacent sequences: A257339 A257340 A257341 * A257343 A257344 A257345

Keyword

nonn,cons

Author

N. J. A. Sloane, Apr 27 2015

Extensions

More terms from Chai Wah Wu, Apr 29 2015

Status

approved