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A284150 Sum_{d|n, d==1 or 4 mod 5} d.

%I A284150 #19 Mar 24 2017 10:21:00
%S A284150 1,1,1,5,1,7,1,5,10,1,12,11,1,15,1,21,1,16,20,5,22,12,1,35,1,27,10,19,
%T A284150 30,7,32,21,12,35,1,56,1,20,40,5,42,42,1,60,10,47,1,51,50,1,52,31,1,
%U A284150 70,12,75,20,30,60,11,62,32,31,85,1,84,1,39,70,15,72,80,1
%N A284150 Sum_{d|n, d==1 or 4 mod 5} d.
%H A284150 Seiichi Manyama, <a href="/A284150/b284150.txt">Table of n, a(n) for n = 1..10000</a>
%F A284150 a(n) = A284097(n) + A284103(n). - _Seiichi Manyama_, Mar 24 2017
%p A284150 A284150 := proc(n)
%p A284150     a := 0 ;
%p A284150     for d in numtheory[divisors](n) do
%p A284150         if modp(d,5) in {1,4} then
%p A284150             a := a+d ;
%p A284150         end if;
%p A284150     end do:
%p A284150     a ;
%p A284150 end proc: # _R. J. Mathar_, Mar 21 2017
%t A284150 Table[Sum[If[Mod[d, 5] == 1 || Mod[d,5]==4, d, 0], {d, Divisors[n]}], {n, 80}] (* _Indranil Ghosh_, Mar 21 2017 *)
%o A284150 (PARI) for(n=1, 80, print1(sumdiv(n, d, if(d%5==1 || d%5 ==4, d, 0)), ", ")) \\ _Indranil Ghosh_, Mar 21 2017
%o A284150 (Python)
%o A284150 from sympy import divisors
%o A284150 def a(n): return sum([d for d in divisors(n) if d%5==1 or d%5 == 4]) # _Indranil Ghosh_, Mar 21 2017
%Y A284150 Cf. A003114, A284097, A284103.
%Y A284150 Cf. Sum_{d|n, d==1 or k-1 mod k} d: A046913 (k=3), A000593 (k=4), this sequence (k=5), A186099 (k=6), A284151 (k=7).
%K A284150 nonn
%O A284150 1,4
%A A284150 _Seiichi Manyama_, Mar 21 2017