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A331260 Denominator of harmonic mean of 3 consecutive primes. Numerators are A331259. 1
31, 71, 167, 311, 551, 791, 1151, 1655, 2279, 3119, 3935, 4871, 5711, 6791, 2797, 9959, 11639, 13175, 14831, 16559, 18383, 20975, 24071, 27419, 30191, 32231, 33911, 36071, 40511, 45791, 51983, 55199, 60167, 64199, 69599, 24637, 79031, 84311, 29917, 94679 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..40.

FORMULA

a(n) = denominator ((3*p1*p2*p3)/(p2*p3 + p1*p3 + p1*p2)) with p1 = prime(n), p2 = prime(n + 1), p3 = prime(n + 2).

EXAMPLE

See A331259.

PROG

(PARI) hm3(x, y, z)=3/(1/x+1/y+1/z);

p1=2; p2=3; forprime(p3=5, 190, print1(denominator(hm3(p1, p2, p3)), ", "); p1=p2; p2=p3)

CROSSREFS

Cf. A046301, A127345, A292530, A331259.

Sequence in context: A237992 A139975 A050957 * A127345 A127346 A089704

Adjacent sequences:  A331257 A331258 A331259 * A331261 A331262 A331263

KEYWORD

nonn,frac

AUTHOR

Hugo Pfoertner, Jan 19 2020

STATUS

approved

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Last modified November 30 19:02 EST 2021. Contains 349424 sequences. (Running on oeis4.)