1,1

The prime factors of 735 are 3,5,7, the sum of whose cubes = 495 = sum of the squares of the digits of 735; so 735 is a term of the sequence.

f[n_] := Module[{a, l, t, r}, a = FactorInteger[n]; l = Length[a]; t = Table[a[[i]][[1]], {i, 1, l}]; r = Sum[(t[[i]])^3, {i, 1, l}]]; g[n_] := Module[{b, m, s}, b = IntegerDigits[n]; m = Length[b]; s = Sum[(b[[i]])^3, {i, 1, m}]]; Select[Range[2, 10^6], f[ # ] == g[ # ] &]

Cf. A006753.

Sequence in context: A122764 A064157 A067184 this_sequence A090719 A088297 A052024

Adjacent sequences: A067167 A067168 A067169 this_sequence A067171 A067172 A067173

base,nonn

Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Feb 18 2002