A227348 Nonsquarefree integers m such that, for prime p, if p^k | m then 1+p^k | 1+m.
26999, 122499, 193599, 599975, 2206775, 2620175, 3501575, 4798079, 8278599, 11631059, 14242175, 16956575, 17578799, 19048799, 49061375, 55504175, 57354725, 70963775, 75271559, 107499699, 114930639, 153536525, 165887189, 202729175, 241430399, 248688719, 257552735, 258969887, 275089919
Offset: 1
Keywords
Examples
26999 = 49*19*29 is in the list because 27000 is divisible by 8,50,20 and 30; 193599 = 9*49*439 is in the list because 193600 is divisible by 4,10,8, 50,440.
Crossrefs
Cf. A056729.
Programs
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Mathematica
PPDivs[m_Integer]:=Module[{f=FactorInteger[m]},Flatten[Table[First[f[[i]]]^Range[Last[f[[i]]]],{i,1,Length[f]}]]]; Select[Select[ Range[1000000], !SquareFreeQ[#]&], Union[ Mod[#+1, 1+PPDivs[#] ] ]== {0} &]
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