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A163100 Triangle giving positive values of A147861. 8
1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, 3, 1, 1, 2, 2, 1, 1, 1, 1, 2, 3, 3, 2, 1, 1, 1, 1, 2, 2, 1, 1, 3, 3, 1, 1, 2, 4, 2, 1, 1, 1, 1, 2, 3, 3, 2, 1, 1, 1, 1, 2, 4, 4, 2, 1, 1, 3, 3, 1, 1, 2, 2, 1, 1, 1, 1, 2, 3, 4, 4, 3, 2, 1, 1, 5, 1, 1, 2, 2, 1, 1, 3, 3, 1, 1, 2, 4, 4, 2, 1, 1, 1, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

Table of n, a(n) for n=1..105.

Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos

Omar E. Pol, Illustration: Divisors and pi(x)

EXAMPLE

Triangle begins:

1;

1,1;

1,..1;

1,2,..1;

1,......1;

1,2,2,....1;

1,..........1;

1,2,..2,......1;

1,..3,..........1;

1,2,....2,........1;

1,..................1;

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

1,......................1;

1,2,........2,............1;

1,..3,..3,..................1;

1,2,..4,......2,..............1;

1,..............................1;

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

1,..................................1;

1,2,..4,4,........2,..................1;

1,..3,......3,..........................1;

1,2,................2,....................1;

1,..........................................1;

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

1,......5,......................................1;

1,2,....................2,........................1;

1,..3,..........3,..................................1;

1,2,..4,....4,............2,..........................1;

1,......................................................1;

1,2,3,..5,5,......3,........2,............................1;

...

Row sums: A117004.

MAPLE

A147861 := proc(n, k) if k<=0 or k > n then 0; else if n mod k = 0 then min(k, n/k) ; else 0; fi; fi; end proc: A163100 := proc(n, k) local dvs; dvs := sort(convert(numtheory[divisors](n), list)) ; min( op(k, dvs), n/op(k, dvs)) ; end: for n from 1 to 60 do for k from 1 to numtheory[tau](n) do printf("%d, ", A163100(n, k) ) ; end do; end do: # R. J. Mathar, Aug 01 2009

CROSSREFS

Cf. A000005, A008578, A027750, A051731, A117004, A127093, A147861, A161345, A161424, A161835, A162526, A162527, A162528, A162529, A162530, A162531, A162532.

Sequence in context: A030419 A155052 A096284 * A139038 A322812 A259094

Adjacent sequences:  A163097 A163098 A163099 * A163101 A163102 A163103

KEYWORD

easy,nonn,tabf

AUTHOR

Omar E. Pol, Jul 20 2009

EXTENSIONS

Extended beyond row 12 by R. J. Mathar, Aug 01 2009

STATUS

approved

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Last modified October 15 09:22 EDT 2019. Contains 328026 sequences. (Running on oeis4.)