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A250033 a(n) gives the denominators for A250031(n) as well as for A250032(n). 5
1, 2, 2, 24, 15, 45, 35, 280, 630, 2100, 2310, 27720, 10010, 140140, 150150, 480480, 255255, 2297295, 4849845, 96996900, 101846745, 106696590, 111546435, 669278610, 929553625, 966735770, 1003917915, 3123300180, 3234846615, 48522699225, 100280245065, 1604483921040, 6618496174290, 6819056664420, 7019617154550, 7220177644680 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See the comments in sequences A250031 and A250032.

LINKS

Stanislav Sykora, Table of n, a(n) for n = 1..1000

S. Sykora, On some number densities related to coprimes, Stan's Library, Vol.V, Nov 2014, DOI: 10.3247/SL5Math14.005

FORMULA

a(n)=A250031(n)+A250032(n).

PROG

(PARI) s_aux(n, p0, inp)={my(t=0/1, tt=0/1, in=inp, pp); while(1, pp=p0*prime(in); tt=n\pp; if(tt==0, break, t+=tt/pp-s_aux(n, pp, in++))); return(t)};

s(n)=1+s_aux(n, 1, 1);

a=vector(1000, n, denominator(s(n-1)/n))

CROSSREFS

Cf. A250031, A250032.

Sequence in context: A048648 A229334 A120065 * A224479 A279311 A248812

Adjacent sequences:  A250030 A250031 A250032 * A250034 A250035 A250036

KEYWORD

nonn,frac

AUTHOR

Stanislav Sykora, Nov 16 2014

STATUS

approved

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Last modified August 17 23:58 EDT 2017. Contains 290682 sequences.