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A381836 k/25 is in this list if A053824(k) < A112765(k), i.e. if digitsum(k, 5) < valuation(k, 5).

%I A381836 #10 Mar 09 2025 12:57:47
%S A381836 1,5,10,25,30,50,75,125,130,150,175,250,275,375,500,625,630,650,675,
%T A381836 750,775,875,1000,1250,1275,1375,1500,1875,2000,2500,3125,3130,3150,
%U A381836 3175,3250,3275,3375,3500,3750,3775,3875,4000,4375,4500,5000,5625,6250,6275,6375
%N A381836 k/25 is in this list if A053824(k) < A112765(k), i.e. if digitsum(k, 5) < valuation(k, 5).
%p A381836 aList := upto -> local k; [seq(k/25, k in select(n -> add(convert(n, base, 5)) < padic[ordp](n, 5), [seq(25..upto,25)]))]: aList(160000);
%t A381836 Select[Range[160000],DigitSum[#,5]<IntegerExponent[#,5] &]/25 (* _Stefano Spezia_, Mar 08 2025 *)
%o A381836 (SageMath)
%o A381836 def aList(upto, b): return [n/b^2 for n in srange(b^2, upto, b^2) if sum(n.digits(b)) < valuation(n, b)]
%o A381836 print(aList(160000, 5))
%Y A381836 Cf. A053824, A112765.
%Y A381836 Cf. A371176 (base 2), A381838 (base 3), A381837 (base 4).
%K A381836 nonn,base
%O A381836 1,2
%A A381836 _Peter Luschny_, Mar 08 2025