A217390 -id:A217390 - cp's OEIS frontend

A217531 Numbers n such that sum of cubes of digits of n equals the sum of prime divisors of n.

142, 402, 5505, 6127, 7305, 12643, 13550, 21033, 21452, 22244, 22290, 22532, 24030, 24936, 25612, 28132, 32040, 35125, 35296, 43053, 47835, 51404, 51703, 52324, 55869, 66003, 69060, 80125, 82464, 86833, 101061, 102240, 103039, 104647, 110334, 110616, 111153

Offset: 1

Michel Lagneau, Oct 05 2012

n such that A055012 (n) = A008472(n).

			402 =  2*3*67  is in the sequence because 4^3 + 0^3 + 2^3 = 2 + 3 + 67 = 72.

Cf. A055012, A008472, A217390.

Rest[Select[Range[20000], Total[Transpose[FactorInteger[#]][[1]]]==Total[IntegerDigits[#]^3]&]]

A240387 Least k such that sum of n-th power of digits of k equals sum of prime divisors of k.

Original entry on oeis.org

2, 12, 142, 210, 22011, 210120, 101220, 11012210, 2202120, 11210021221, 1100200012, 1000200000111, 1211201222, 211222020, 101101001120

Offset: 1

Michel Lagneau, Apr 04 2014

a(16) <= 1001110220200020. - Giovanni Resta, Apr 07 2014

			a(5) = 22011 =  3*11*23*29 because 2^5 + 2^5 + 0^5 + 1^5 + 1^5 = 3 + 11 + 23 + 29 = 66.

Cf. A008472, A217390, A217531, A217532, A217533.

Do[k=2;While[!Total[Transpose[FactorInteger[k]][[1]]]==Total[IntegerDigits[k]^n],k++];Print[n," ",k],{n,1,15}]

cp's OEIS Frontend

A217531 Numbers n such that sum of cubes of digits of n equals the sum of prime divisors of n.

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