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A071804
Number of pairs (x,y) such that tau(x^y) = x+y, 1<=x<=n, 1<=y<=n.
0
0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9
OFFSET
1,9
PROG
(PARI) for(n=1, 130, print1(sum(i=1, n, sum(j=1, n, if(numdiv(i^j)-i-j, 0, 1))), ", "))
CROSSREFS
Cf. A000005.
Sequence in context: A067100 A296237 A074802 * A280953 A111894 A279012
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jun 06 2002
STATUS
approved