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A076381 Numbers n such that sum of digits in base 3 is a divisor of sum of prime divisors (A008472). 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

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;

MATHEMATICA

Select[Range[2, 400], Divisible[Total[FactorInteger[#][[All, 1]]], Total[ IntegerDigits[ #, 3]]]&] (* Harvey P. Dale, Jul 09 2018 *)

CROSSREFS

Cf. A075657, A076380 - A076387.

Sequence in context: A088220 A085612 A073915 * A282571 A063455 A001144

Adjacent sequences:  A076378 A076379 A076380 * A076382 A076383 A076384

KEYWORD

nonn,base

AUTHOR

Floor van Lamoen, Oct 08 2002

STATUS

approved

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Last modified August 24 18:12 EDT 2019. Contains 326295 sequences. (Running on oeis4.)