cp's OEIS Frontend

A220000 Sixty fourths of an inch in thousandths, rounded to nearest integer.

%I A220000 #23 Jun 28 2023 07:49:14
%S A220000 16,31,47,63,78,94,109,125,141,156,172,188,203,219,234,250,266,281,
%T A220000 297,313,328,344,359,375,391,406,422,438,453,469,484,500,516,531,547,
%U A220000 563,578,594,609,625,641,656,672,688,703,719,734,750,766,781
%N A220000 Sixty fourths of an inch in thousandths, rounded to nearest integer.
%C A220000 Diameter of successive drill bits, in thousandths of an inch, within an ordered set consisting of increments of 1/64th of an inch. Traditionally the sizes of bits in such a set are expressed in simplest reduced fractional inch values: 1/64, 1/32, 3/64, 1/16, etc. Of fundamental importance to machinists, tool and die makers, carpenters, hobbyists, insomnial science teachers, etc.
%D A220000 Jack Erjavec, Automotive Technology, 2010, pages 66-73.
%D A220000 Frank D. Graham, Audels Machinists and Tool Makers Handy Book, 1941, pages 34-48.
%D A220000 IBM Corp., Precision Measurement in the Metal Working Industry, 1939, page 11.
%H A220000 Hamuniverse, <a href="http://www.hamuniverse.com/antfrac.html">Handy Table for Measurements and Conversions</a>
%H A220000 JGB Enterprises, <a href="http://www.jgbhose.com/Data_Returns/fraction_chart.asp">Fraction-Decimal Conversion Chart</a>
%H A220000 Kellog Community College, <a href="http://academic.kellogg.edu/cad/pdf/decimal_chart.pdf">Fraction/Decimal/Conversion Chart</a>
%H A220000 Moam, Inc., <a href="http://www.moam-inc.com/DECIMAL_EQ_CHART.pdf">Decimal Equivalents: Fractions-Inches-Millimeters-Points</a>
%H A220000 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,1,-1).
%F A220000 a(n) = round(125*n/8), with 0.5 rounded up.
%e A220000 For n = 5 the a(5) term = (5/64)*1000 = 78.125, which is rounded to 78.
%t A220000 Table[Floor[1000 n/64+1/2],{n,64}] (* _Harvey P. Dale_, Jan 13 2020 *)
%o A220000 (PARI) a(n)=(125*n+4)\8 \\ _Charles R Greathouse IV_, Dec 06 2012
%Y A220000 Cf. A085269, A029919, A029920, A169860, A169861.
%K A220000 nonn,easy
%O A220000 1,1
%A A220000 _Marc Alan Rosner_, Dec 03 2012