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A164009 Zero together with row 9 of the array in A163280. 4
0, 19, 38, 51, 76, 75, 114, 105, 136, 162, 190, 209, 264, 273, 308, 345, 384, 425, 468, 513, 560, 609, 660, 713, 768, 825, 884, 945, 1008, 1073, 1140, 1209, 1280, 1353, 1428, 1505, 1584, 1665, 1748, 1833, 1920, 2009, 2100, 2193, 2288, 2385, 2484, 2585, 2688 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..48.

Index entries for linear recurrences with constant coefficients, signature (3, -3, 1).

FORMULA

Conjecture: a(n) = A028566(n), n > 12. [R. J. Mathar, Jul 31 2010]

MAPLE

A033676 := proc(n) local dvs; dvs := sort(convert(numtheory[divisors](n), list)) ; op(floor((nops(dvs)+1)/2) , dvs) ; end proc:

A163280 := proc(n, k) local r, T ; r := 0 ; for T from k^2 by k do if A033676(T) = k then r := r+1 ; if r = n then return T ; end if; end if; end do: end proc:

printf("0, ") ; for n from 1 to 90 do printf("%d, ", A163280(9, n)) ; end do ; # R. J. Mathar, Jul 31 2010

CROSSREFS

Cf. A008578, A161344, A161345, A163280, A164000, A164008, A164010.

Sequence in context: A067205 A196185 A040342 * A235030 A048844 A008601

Adjacent sequences:  A164006 A164007 A164008 * A164010 A164011 A164012

KEYWORD

nonn

AUTHOR

Omar E. Pol, Aug 08 2009

EXTENSIONS

Terms beyond a(12) from R. J. Mathar, Jul 31 2010

STATUS

approved

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Last modified June 24 22:04 EDT 2019. Contains 324337 sequences. (Running on oeis4.)