A192034 - OEIS

A192034

Least k such that (product of proper divisors of k) mod (sum of proper divisors of k) equals n.

2, 8, 4, 9, 14, 25, 15, 49, 22, 18, 21, 57, 45, 169, 34, 69, 38, 205, 143, 119, 46, 87, 217, 93, 130, 133, 58, 323, 62, 111, 160, 553, 319, 63, 74, 129, 30, 305, 82, 75, 86, 36, 68, 335, 48, 159, 301, 355, 369, 171, 106, 177

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OFFSET

0,1

COMMENTS

Greedy inverse of A191906.

LINKS

Table of n, a(n) for n=0..51.

EXAMPLE

a(0)=2 because A007956(2) mod A001065(2) = 1 mod 1 = 0, and 2 is the smallest number for which this is the case;

a(1)=8 because A007956(8) mod A001065(8) = 8 mod 7 = 1, and 8 is the smallest number for which this is the case;

a(2)=4 because A007956(4) mod A001065(4) = 2 mod 3 = 2, and 4 is the smallest number for which this is the case.

MAPLE

A192034 := proc(n) local k ; for k from 2 do if A191906(k) = n then return k ; end if; end do: end proc: # R. J. Mathar, Jul 01 2011

MATHEMATICA

ds[n_]:=Module[{divs=Most[Divisors[n]]}, Mod[Times@@divs, Total[divs]]]; Join[ {2}, Transpose[Table[SelectFirst[Table[{n, ds[n]}, {n, 2, 2000}], #[[2]] == i&], {i, 60}]][[1]]] (* Harvey P. Dale, Apr 11 2015 *)

CROSSREFS

Cf. A001065, A007956, A191906.

Sequence in context: A021355 A323986 A334447 * A209874 A175181 A110003

Adjacent sequences: A192031 A192032 A192033 * A192035 A192036 A192037

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jun 21 2011

EXTENSIONS

Corrected by R. J. Mathar, Jul 01 2011

Example section corrected by Jon E. Schoenfield, Feb 24 2019

STATUS

approved