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A021141 Decimal expansion of 1/137. 1
0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7, 2, 9, 9, 2, 7, 0, 0, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Until the middle of the 20th century, the so-called "fine structure constant", a most important dimensionless physical constant, was widely supposed to be exactly 1/137.

LINKS

Table of n, a(n) for n=0..98.

Wikipedia, Fine-structure constant (Numerological explanations)

FORMULA

a(n) = (1/56)*(58*(n mod 8) - 26*((n+1) mod 8) + 58*((n+2) mod 8) + 9*((n+3) mod 8) - 40*((n+4) mod 8) + 44*((n+5) mod 8) - 40*((n+6) mod 8) + 9*((n+7) mod 8)). [Paolo P. Lava, Sep 21 2009]

MATHEMATICA

PadLeft[First@ #, Abs@ Last@ # + Length@ First@ #] &@ RealDigits[N[1/137, 120]] (* Bruno Berselli, Jun 21 2016 *)

CROSSREFS

Sequence in context: A156547 A180872 A003673 * A246948 A248283 A147677

Adjacent sequences:  A021138 A021139 A021140 * A021142 A021143 A021144

KEYWORD

nonn,cons,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified February 17 11:57 EST 2019. Contains 320219 sequences. (Running on oeis4.)