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A358228 Numbers k such that A276086(k) mod A003415(k) is an odd number, where A003415 is the arithmetic derivative and A276086 is the primorial base exp-function.

%I A358228 #7 Nov 25 2022 11:10:27
%S A358228 4,8,10,12,14,16,20,22,24,28,30,32,36,40,42,44,48,50,52,54,56,58,60,
%T A358228 62,63,64,66,68,72,74,75,76,78,80,84,88,90,92,96,98,99,100,102,104,
%U A358228 108,110,112,114,116,120,122,124,126,128,132,136,138,140,144,148,150,152,154,156,158,160,162,164,168,171,172,176
%N A358228 Numbers k such that A276086(k) mod A003415(k) is an odd number, where A003415 is the arithmetic derivative and A276086 is the primorial base exp-function.
%H A358228 <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%o A358228 (PARI)
%o A358228 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A358228 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
%o A358228 A358227(n) = ((A276086(n)%A003415(n))%2);
%o A358228 isA358228(n) = A358227(n);
%Y A358228 Complement: {1} U A358229.
%Y A358228 Cf. A003415, A276086, A328382, A358228 (characteristic function), A358232 (subsequence).
%Y A358228 Cf. also A358225.
%K A358228 nonn
%O A358228 1,1
%A A358228 _Antti Karttunen_, Nov 25 2022