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A143614
Triangle read by rows: A054521 * A051731 as infinite lower triangular matrices.
1
1, 1, 0, 2, 1, 0, 2, 0, 1, 0, 4, 2, 1, 1, 0, 2, 0, 0, 0, 1, 0, 6, 3, 2, 1, 1, 1, 0, 4, 0, 1, 0, 1, 0, 1, 0, 6, 3, 0, 2, 1, 0, 1, 1, 0, 4, 0, 2, 0, 0, 0, 1, 0, 1, 0, 10, 5, 3, 2, 2, 1, 1, 1, 1, 1, 0, 4, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 12, 6, 4, 3, 2, 2, 1, 1, 1, 1, 1, 1, 0, 6, 0, 2, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0
OFFSET
1,4
COMMENTS
Left border = phi(n), A000010: (1, 1, 2, 2, 4, 2, 6,...).
Row sums = A143615: (1, 1, 3, 3, 8, 3, 14, 7,...).
FORMULA
A054521 records the relative primes of n, indicated by a 1's in row n, 0 otherwise. A051731 = the inverse Moebius transform, in which 1's by rows indicate the divisors of n, 0 otherwise.
EXAMPLE
First few rows of the triangle =
1;
1, 0;
2, 1, 0;
2, 0, 1, 0;
4, 2, 1, 1, 0;
2, 0, 0, 0, 1, 0;
6, 3, 2, 1, 1, 1, 0;
4, 0, 1, 0, 1, 0, 1, 0;
6, 3, 0, 2, 1, 0, 1, 1, 0;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Aug 27 2008
EXTENSIONS
a(96) and a(101) split by Georg Fischer, May 29 2023
STATUS
approved