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A071227
Number of solutions 1<=x<=m to gcd(m,x) = tau(m) where m = A033950(n).
0
1, 1, 1, 2, 1, 2, 2, 2, 4, 6, 4, 2, 4, 6, 10, 4, 12, 6, 8, 10, 16, 18, 12, 4, 22, 16, 20, 18, 28, 4, 30, 6, 22, 8, 36, 40, 42, 28, 8, 30, 46, 8, 10, 52, 42, 36, 16, 20, 12, 58, 8, 60, 40, 12, 42, 66, 12, 46, 70, 72, 20, 16, 100, 78, 52, 16, 82, 12, 18, 58, 88, 8, 60, 96, 20, 66, 100
OFFSET
1,4
PROG
(PARI) for(n=1, 1000, if(sum(i=1, n, if(gcd(n, i)-numdiv(n), 0, 1))>0, print1(sum(i=1, n, if(gcd(n, i)-numdiv(n), 0, 1)), ", ")))
CROSSREFS
Cf. A033950.
Sequence in context: A060169 A117958 A113401 * A285442 A108115 A089254
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Jun 10 2002
EXTENSIONS
Name corrected by Sean A. Irvine, Jul 05 2024
STATUS
approved