A067170 - OEIS

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A067170

Numbers n such that sum of the cubes of the prime factors of n equals the sum of the cubes of the digits of n.

2, 3, 5, 7, 250, 735, 2500, 25000, 250000 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,1`
	EXAMPLE	`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.`
	MATHEMATICA	`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[ # ] &]`
	CROSSREFS	`Cf. A006753.` `Sequence in context: A064157 A178371 A067184 * A090719 A088297 A180015` `Adjacent sequences: A067167 A067168 A067169 * A067171 A067172 A067173`
	KEYWORD	`base,nonn`
	AUTHOR	`Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Feb 18 2002`

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.