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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A358977 Numbers that are coprime to the sum of their primorial base digits (A276150).

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%I A358977 #9 Dec 12 2022 01:34:17
%S A358977 1,2,3,5,6,7,10,11,13,14,15,17,19,21,22,23,26,29,30,31,34,35,37,38,39,
%T A358977 41,43,46,47,49,53,54,55,57,58,59,61,62,63,67,69,71,73,74,78,79,81,82,
%U A358977 83,85,86,87,89,91,93,94,95,97,98,101,102,103,106,107,109,110
%N A358977 Numbers that are coprime to the sum of their primorial base digits (A276150).
%C A358977 Numbers k such that gcd(k, A276150(k)) = 1.
%C A358977 The primorial numbers (A002110) are terms. These are also the only primorial base Niven numbers (A333426) in this sequence.
%C A358977 Includes all the prime numbers.
%C A358977 The numbers of terms not exceeding 10^k, for k = 1, 2, ..., are 7, 59, 603, 6047, 60861, 608163, 6079048, 60789541, 607847981, 6080015681... . Conjecture: The asymptotic density of this sequence exists and equals 6/Pi^2 = 0.607927... (A059956), the same as the density of A094387.
%H A358977 Amiram Eldar, <a href="/A358977/b358977.txt">Table of n, a(n) for n = 1..10000</a>
%e A358977 3 is a term since A276150(3) = 2, and gcd(3, 2) = 1.
%t A358977 With[{max = 4}, bases = Prime@Range[max, 1, -1]; nmax = Times @@ bases - 1; sumdig[n_] := Plus @@ IntegerDigits[n, MixedRadix[bases]]; Select[Range[nmax], CoprimeQ[#, sumdig[#]] &]]
%o A358977 (PARI) is(n) = {my(p=2, s=0, m=n, r); while(m>0, r = m%p; s+=r; m\=p; p = nextprime(p+1)); gcd(n, s)==1; }
%Y A358977 Cf. A059956, A276150, A333426.
%Y A358977 Subsequences: A000040, A002110.
%Y A358977 Similar sequences: A094387, A339076, A358975, A358976, A358978.
%K A358977 nonn,base
%O A358977 1,2
%A A358977 _Amiram Eldar_, Dec 07 2022