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A063848
Numbers k such that mu(k) + mu(k+1) + mu(k+2) = 2.
1
14, 20, 32, 34, 38, 55, 56, 84, 86, 91, 92, 94, 117, 118, 121, 122, 132, 133, 140, 142, 143, 144, 145, 158, 159, 176, 183, 200, 202, 203, 204, 205, 208, 212, 214, 215, 216, 218, 219, 235, 247, 252, 297, 298, 299, 300, 302, 303, 319, 325, 326, 327, 328, 333
OFFSET
1,1
LINKS
MATHEMATICA
Flatten[Position[Partition[MoebiusMu[Range[350]], 3, 1], _?(Total[#]==2&), {1}, Heads->False]] (* Harvey P. Dale, Nov 26 2015 *)
PROG
(PARI) m(n) = moebius(n)+moebius(n+1)+moebius(n+2);
j=[]; for(n=1, 1000, if(m(n)==2, j=concat(j, n))); j
(PARI) M(n) = moebius(n) + moebius(n + 1) + moebius(n + 2)
{ n=0; for (m=1, 10^9, if(M(m)==2, write("b063848.txt", n++, " ", m); if (n==1000, break)) ) } \\ Harry J. Smith, Sep 01 2009
CROSSREFS
Cf. A063838.
Sequence in context: A186193 A285426 A108874 * A110968 A054017 A129216
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Aug 26 2001
STATUS
approved