A110084 Numbers n with even length such that sigma(n)=d_1^d_2*d_3^d_4 *...*d_(k-1)^d_k where d_1 d_2 ... d_k is the decimal expansion of n.
146710, 334552, 12931485, 15734393, 16839254, 20499191, 28661422, 38722820, 43681330, 44463034, 45509442, 55188392, 55938216, 92505149, 1054662422, 1060804965, 1068721252, 1094834272, 1167528360, 1341465139, 1436725284, 1452198772, 1452847236, 1540709585, 1594291529, 1596602643, 1672853710
Offset: 1
Examples
45509442 is in the sequence because sigma(55938216)=5^5*9^3*8^2*1^6.
Links
- Max Alekseyev, Table of n, a(n) for n = 1..99
Programs
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Mathematica
Do[h = IntegerDigits[n]; k = Length[h]; If[EvenQ[k] && Select[ Range[k/2], h[[2#-1]] == 0 &] == {} && DivisorSigma[1, n]== Product[h[[2j-1]]^h[[2j]], {j, k/2}], Print[n]], {n, 10^8}]
Extensions
Terms a(14) onward from Max Alekseyev, Oct 16 2012