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A227107 Numerators of harmonic mean H(n,4), n >= 0. 2
0, 8, 8, 24, 4, 40, 24, 56, 16, 72, 40, 88, 6, 104, 56, 120, 32, 136, 72, 152, 20, 168, 88, 184, 48, 200, 104, 216, 7, 232, 120, 248, 64, 264, 136, 280, 36, 296, 152, 312, 80, 328, 168, 344, 22, 360, 184, 376, 96, 392, 200, 408, 52, 424, 216 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(n) = numerator(H(n,4)) = numerator(8*n/(n+4)), n>=0, with H(n,4) the harmonic mean of n and 4.

The corresponding denominators are given in A000265(n+4), n >= 0.

a(n+4), n>=0, is the fourth column (m=4) of the triangle A227041.

LINKS

Table of n, a(n) for n=0..54.

FORMULA

a(n) = numerator(8*n/(n+4)), n >= 0.

a(n) = 8*n/gcd(n+4,8*n) = 8*n/gcd(n+4,32), n >= 0.

EXAMPLE

The rationals H(n,4) begin: 0, 8/5, 8/3, 24/7, 4, 40/9, 24/5, 56/11, 16/3, 72/13, 40/7, 88/15, 6, 104/17, 56/9, 120/19, ...

CROSSREFS

Cf. A227041(n+4,4), A227140(n+8) (denominators), n >= 0.

Sequence in context: A299592 A061156 A195862 * A205382 A109049 A160239

Adjacent sequences:  A227104 A227105 A227106 * A227108 A227109 A227110

KEYWORD

nonn,frac,easy

AUTHOR

Wolfdieter Lang, Jul 01 2013

STATUS

approved

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Last modified February 17 22:32 EST 2018. Contains 299297 sequences. (Running on oeis4.)