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A127449 Triangle T(n,k) = n if gcd(n,k)=1, =0 otherwise. 0
1, 2, 0, 3, 3, 0, 4, 0, 4, 0, 5, 5, 5, 5, 0, 6, 0, 0, 0, 6, 0, 7, 7, 7, 7, 7, 7, 0, 8, 0, 8, 0, 8, 0, 8, 0, 9, 9, 0, 9, 9, 0, 9, 9, 0, 10, 0, 10, 0, 0, 0, 10, 0, 10, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..55.

FORMULA

T(n,k) = n *A054521(n,k), 1<=k<=n.

EXAMPLE

First few rows of the triangle are:

1;

2, 0;

3, 3, 0;

4, 0, 4, 0;

5, 5, 5, 5, 0;

6, 0, 0, 0, 6, 0;

7, 7, 7, 7, 7, 7, 0;

...

CROSSREFS

Cf. A002618 (row sums), A054521.

Sequence in context: A004557 A088276 A099838 * A328911 A138057 A053727

Adjacent sequences:  A127446 A127447 A127448 * A127450 A127451 A127452

KEYWORD

nonn,tabl,easy

AUTHOR

Gary W. Adamson, Jan 14 2007

STATUS

approved

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Last modified July 25 16:03 EDT 2021. Contains 346291 sequences. (Running on oeis4.)