cp's OEIS Frontend

A344698 a(n) = A344696(A108951(n)).

%I A344698 #11 May 29 2021 20:01:29
%S A344698 1,1,1,7,1,7,1,5,91,7,1,5,1,7,91,31,1,65,1,5,91,7,1,31,2821,7,25,5,1,
%T A344698 65,1,21,91,7,2821,403,1,7,91,31,1,65,1,5,25,7,1,21,7657,403,91,5,1,
%U A344698 155,2821,31,91,7,1,403,1,7,25,127,2821,65,1,5,91,403,1,91,1,7,155,5,7657,65,1,21,3751,7,1,403,2821
%N A344698 a(n) = A344696(A108951(n)).
%C A344698 Records seem to occur on certain squares: 1, 4, 9, 25, 49, 100, 121, 289, 361, 529, 841, 961, etc. See A344701.
%H A344698 Antti Karttunen, <a href="/A344698/b344698.txt">Table of n, a(n) for n = 1..10201</a>
%H A344698 <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>
%H A344698 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%o A344698 (PARI)
%o A344698 A034386(n) = prod(i=1, primepi(n), prime(i));
%o A344698 A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };  \\ From A108951
%o A344698 A001615(n) = if(1==n,n, my(f=factor(n)); prod(i=1, #f~, f[i, 1]^f[i, 2] + f[i, 1]^(f[i, 2]-1))); \\ After code in A001615
%o A344698 A344696(n) = { my(u=sigma(n)); (u/gcd(u,A001615(n))); };
%o A344698 A344698(n) = A344696(A108951(n));
%Y A344698 Cf. A000203, A001615, A108951, A337203, A344696, A344699, A344701 (positions of records).
%K A344698 nonn
%O A344698 1,4
%A A344698 _Antti Karttunen_, May 26 2021