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A068510 LCM(1,...,n) - (product of primes <= n). 2
0, 0, 0, 6, 30, 30, 210, 630, 2310, 2310, 25410, 25410, 330330, 330330, 330330, 690690, 11741730, 11741730, 223092870, 223092870, 223092870, 223092870, 5131136010, 5131136010, 26548051530, 26548051530, 80090340330, 80090340330 (list; graph; refs; listen; history; internal format)
OFFSET

1,4

LINKS

T. D. Noe, Table of n, a(n) for n=1..200

MAPLE

a[1] := 0:a[2] := 0:l := 2:p := 3:pp := 2:for i from 3 to 50 do l := ilcm(l, i): if(p=i) then pp := pp*p:p := nextprime(p):end if: a[i] := l-pp:end do:q := seq(a[j], j=1..50);

MATHEMATICA

f[n_] := (LCM @@ Table[i, {i, n}] - Product[Prime[i], {i, PrimePi[n]}]); Table[f[n], {n, 30}]

CROSSREFS

Cf. A059794, A068511.

Sequence in context: A123624 A066197 A078638 * A147798 A197880 A175497

Adjacent sequences:  A068507 A068508 A068509 * A068511 A068512 A068513

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Mar 21 2002

EXTENSIONS

More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Mar 23 2002

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Last modified February 16 02:51 EST 2012. Contains 205860 sequences.