A088824 Numbers n such that the sum of smallest prime factors of numbers from 1 to n is divisible by n.

1, 2, 7, 14, 78, 113, 153, 439, 462, 1215, 2294, 8363, 11102, 12302, 36382, 38370, 60398, 199953, 224090, 421399, 427131, 1947938, 2467022, 2571633, 62395623, 462027217, 2140648015, 6418011931, 43074345625, 52714450814, 71229445182, 90719472005, 105685014433

Offset: 1

Author

Labos Elemer, Oct 22 2003

Keywords

• nonn

Links

• Giovanni Resta, Table of n, a(n) for n = 1..38 (terms < 7.5*10^12)

Crossrefs

Cf. A088821-A088825.

Programs

Mathematica

smp[n_] := If[n==1, 0, FactorInteger[n][[1, 1]]]; s = Accumulate @ Array[ smp, 10^5]; Select[Range[10^5], Mod[s[[#]], #] == 0 &] (* Giovanni Resta, Apr 27 2017 *)

Formula

Solutions to Mod[A088821[x], x]=0.

Extensions

More terms from Ray Chandler, Oct 31 2003

a(27)-a(31) from Donovan Johnson, Jul 09 2010

a(32)-a(33) from Giovanni Resta, Apr 27 2017