A218539 Numbers that are equal to the sum of the uniform platonic polyhedral (figurate) numbers (tetrahedral, cubic, octahedral, dodecahedral, or icosahedral) on each of their digits.
0, 1, 20, 21, 24, 153, 240, 241, 289, 304, 324, 370, 371, 407, 440, 441, 593, 739, 2167, 2284, 2348, 2484, 2583, 2860, 2861, 3009, 3029, 3093, 3249, 4288, 5859, 6888, 7996, 9898
Offset: 1
Examples
The octahedral numbers are represented by the formula, y(x)=(2x^3+x)/3; apply this formula to each of the digits in a(18)=739, i.e., y(7)=231, y(3)=19, y(9)=489; sum=739; the dodecahedral numbers are represented by the formula, y(x)=x(3x-1)(3x-2)/2; apply this formula to each of the digits in a(34)=9898, i.e., y(9)=2725, y(8)=2024; y(9)=2725, y(8)=2024; sum=9898.
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