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A130158 Table read by rows in which row n lists the positive divisors of A130157(n). 2
1, 1, 1, 2, 1, 3, 1, 3, 1, 5, 1, 2, 4, 1, 7, 1, 2, 3, 6, 1, 3, 9, 1, 3, 9, 1, 11, 1, 3, 9, 1, 2, 5, 10, 1, 2, 7, 14, 1, 13, 1, 2, 4, 8, 16, 1, 11, 1, 2, 3, 4, 6, 12, 1, 7, 1, 2, 4, 5, 10, 20, 1, 2, 7, 14, 1, 3, 5, 15, 1, 23, 1, 2, 4, 8, 16, 1, 17, 1, 2, 13, 26 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..82.

EXAMPLE

Triangle starts:

1;

1;

1, 2;

1, 3;

1, 3;

1, 5;

1, 2, 4;

1, 7;

1, 2, 3, 6;

...

MAPLE

A130158 := proc(nmax) local a130157, a, n, anext, i ; a130157 := [1] ; a := [] ; while nops(a) < nmax do n := nops(a130157)+1 ; a := [op(a), op(numtheory[divisors](op(-1, a130157)))] ; anext :=0 ; for i from 1 to nops(a130157) do if gcd(op(i, a130157), op(n-1, a)) = 1 then anext := anext+1 ; fi ; od ; a130157 := [op(a130157), anext] ; od ; RETURN(a) ; end: A130158(80) ; # R. J. Mathar, Jun 12 2007

CROSSREFS

Cf. A130157.

Sequence in context: A029227 A029214 A134460 * A187497 A104984 A083868

Adjacent sequences:  A130155 A130156 A130157 * A130159 A130160 A130161

KEYWORD

nonn,tabf

AUTHOR

Leroy Quet, May 13 2007

EXTENSIONS

More terms from R. J. Mathar, Jun 12 2007

Edited by Charles R Greathouse IV, Apr 30 2010

Edited by N. J. A. Sloane, May 09 2010

STATUS

approved

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Last modified November 20 10:31 EST 2017. Contains 294963 sequences.