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A159905 Triangle read by rows, Mobius transform of A004736 2
1, 1, 1, 2, 2, 1, 2, 2, 2, 1, 4, 4, 3, 2, 1, 2, 2, 3, 3, 2, 1, 6, 6, 5, 4, 3, 2, 1, 4, 4, 4, 4, 4, 3, 2, 1, 6, 6, 6, 6, 5, 4, 3, 2, 1, 4, 4, 5, 5, 5, 5, 4, 3, 2, 1, 10, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 4, 4, 4, 5, 6, 6, 6, 5, 4, 3, 2, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Row sums = A007438, Mobius transform of the triangular numbers.

Left border = phi(n), A000010.

LINKS

Table of n, a(n) for n=1..78.

FORMULA

Triangle read by rows, A054525 * A004736. A054525 = the Mobius transform, A004736 = the natural number "decrescendo" triangle: (1; 2,1; 3,2,1;...)

EXAMPLE

First few rows of the triangle =

1;

1, 1;

2, 2, 1;

2, 2, 2, 1;

4, 4, 3, 2, 1;

2, 2, 3, 3, 2, 1;

6, 6, 5, 4, 3, 2, 1;

4, 4, 4, 4, 4, 3, 2, 1;

6, 6, 6, 6, 5, 4, 3, 2, 1;

4, 4, 5, 5, 5, 5, 4, 3, 2, 1;

...

CROSSREFS

Cf. A007438

Sequence in context: A168258 A116204 A291592 * A283735 A274534 A224030

Adjacent sequences:  A159902 A159903 A159904 * A159906 A159907 A159908

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Apr 25 2009

STATUS

approved

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Last modified October 19 04:40 EDT 2019. Contains 328211 sequences. (Running on oeis4.)