cp's OEIS Frontend

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.

A322676 Numbers k > 0 such that k has more divisors d, such that d-1 is prime, than any other smaller positive number, with a(1) = 1.

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%I A322676 #21 Dec 17 2024 16:35:40
%S A322676 1,3,6,12,24,48,72,120,168,240,360,720,1440,2160,2520,4320,5040,7560,
%T A322676 10080,15120,20160,27720,30240,55440,75600,83160,110880,151200,166320,
%U A322676 332640,665280,831600,1330560,1441440,1663200,2162160,2882880,3326400,4324320,6486480,8648640
%N A322676 Numbers k > 0 such that k has more divisors d, such that d-1 is prime, than any other smaller positive number, with a(1) = 1.
%C A322676 Position of records in A072627.
%t A322676 DeleteDuplicates[Table[{n,Count[Divisors[n]-1,_?PrimeQ]},{n,87*10^5}],GreaterEqual[#1[[2]],#2[[2]]]&][[;;,1]] (* _Harvey P. Dale_, Dec 17 2024 *)
%o A322676 (PARI) r=-1; for(n=1, 10^6, t=sumdiv(n, d, isprime(d-1)); if(t>r, r=t; print1(n, ", ")));
%Y A322676 Cf. A072627, A202727, A322678.
%K A322676 nonn
%O A322676 1,2
%A A322676 _Daniel Suteu_, Dec 23 2018