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Numbers n such that sum of digits in base 7 is a divisor of sum of prime divisors (A008472).
1

%I #6 Mar 02 2015 16:08:49

%S 2,3,5,7,8,9,42,49,78,84,105,114,115,126,130,154,156,161,168,170,186,

%T 228,235,252,258,294,305,336,343,350,357,366,371,372,378,402,410,425,

%U 429,430,434,442,444,455,456,460,474,504,516,520,555,558,574,588,616

%N Numbers n such that sum of digits in base 7 is a divisor of sum of prime divisors (A008472).

%p A076385 := 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 7); t1 := floor(t1/7); 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;

%Y Cf. A075657, A076380 - A076387.

%K nonn,base

%O 1,1

%A _Floor van Lamoen_, Oct 08 2002