A325795 Numbers with more divisors than the sum of their prime indices.
1, 2, 4, 6, 8, 12, 16, 18, 20, 24, 30, 32, 36, 40, 42, 48, 54, 56, 60, 64, 72, 80, 84, 90, 96, 100, 108, 112, 120, 126, 128, 132, 140, 144, 150, 156, 160, 162, 168, 176, 180, 192, 198, 200, 204, 210, 216, 220, 224, 234, 240, 252, 256, 260, 264, 270, 280, 288
Offset: 1
Keywords
Examples
The sequence of terms together with their prime indices begins: 1: {} 2: {1} 4: {1,1} 6: {1,2} 8: {1,1,1} 12: {1,1,2} 16: {1,1,1,1} 18: {1,2,2} 20: {1,1,3} 24: {1,1,1,2} 30: {1,2,3} 32: {1,1,1,1,1} 36: {1,1,2,2} 40: {1,1,1,3} 42: {1,2,4} 48: {1,1,1,1,2} 54: {1,2,2,2} 56: {1,1,1,4} 60: {1,1,2,3} 64: {1,1,1,1,1,1}
Crossrefs
Programs
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Mathematica
Select[Range[100],DivisorSigma[0,#]>Total[Cases[FactorInteger[#],{p_,k_}:>PrimePi[p]*k]]&]
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