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A171183 Numbers n such that sigmawt(n) = sigmawt(n+1), where sigmawt(n) is the sum of the divisors of n weighted by divisor multiplicity in n. 1
14, 957, 1334, 1634, 2402, 2685, 20145, 33998, 42818, 74918, 79826, 79833, 84134, 111506, 122073, 138237, 147454, 166934, 201597, 274533, 289454, 347738, 383594, 416577, 440013, 544334, 605985, 649154, 655005, 1060802, 1642154, 1674513 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Ray Chandler, Table of n, a(n) for n=1..200

MATHEMATICA

divmult[d_, n_] := Module[{output, i}, If[d == 1, output = 1, If[d == n, output = 1, i = 0; While[Mod[n, d^(i + 1)] == 0, i = i + 1]; output = i]]; output]; dmt[n_] := Module[{divs, l}, divs = Divisors[n]; l = Length[divs]; Sum[divmult[divs[[i]], n]*divs[[i]], {i, 1, l}]]; l = {}; Do[If[dmt[i] == dmt[i + 1], l = Append[l, i]], {i, 1, 10^6}]; l

CROSSREFS

See A168512 for definition of divisor multiplicity.

Sequence in context: A199651 A241110 A055152 * A064729 A189304 A123178

Adjacent sequences:  A171180 A171181 A171182 * A171184 A171185 A171186

KEYWORD

nonn

AUTHOR

Joseph L. Pe, Dec 05 2009

EXTENSIONS

Extended by Ray Chandler, Dec 08 2009

STATUS

approved

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Last modified January 28 06:00 EST 2021. Contains 340490 sequences. (Running on oeis4.)