A076381 Numbers n such that sum of digits in base 3 is a divisor of sum of prime divisors (A008472).
2, 3, 4, 9, 25, 27, 30, 42, 51, 66, 78, 81, 84, 90, 105, 114, 126, 138, 141, 147, 153, 156, 159, 168, 170, 185, 186, 187, 198, 201, 220, 222, 228, 231, 234, 243, 245, 246, 252, 258, 264, 270, 276, 282, 290, 291, 294, 301, 312, 315, 322, 323, 325, 336, 340, 341
Offset: 1
Programs
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Maple
A076381 := proc(n) local i,j,t,t1, sod, sopd; t := NULL; for i from 2 to n do t1 := i; sod := 0; while t1 <> 0 do sod := sod + (t1 mod 3); t1 := floor(t1/3); od; sopd := 0; j := 1; while ithprime(j) <= i do if i mod ithprime(j) = 0 then sopd := sopd+ithprime(j); fi; j := j+1; od; if sopd mod sod = 0 then t := t,i; fi; od; t; end;
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Mathematica
Select[Range[2,400],Divisible[Total[FactorInteger[#][[All,1]]],Total[ IntegerDigits[ #,3]]]&] (* Harvey P. Dale, Jul 09 2018 *)