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Odd bisection of A374431.
1

%I #8 Jul 11 2024 09:38:16

%S 1,3,5,7,27,11,13,30375,17,19,750141,23,3125,19683,29,31,235782657,

%T 1313046875,37,3502727631,41,43,28025208984375,47,823543,634465620819,

%U 53,7863818359375,7971951402153,59,61,422112982235053221,453238525390625

%N Odd bisection of A374431.

%p PF := n -> ifelse(n = 0, {}, NumberTheory:-PrimeFactors(n)):

%p T := (n, k) -> mul(PF(n) intersect PF(k)):

%p seq(mul(T(2*n+1, k), k = 0..2*n+1), n = 0..20);

%t nn = 65; Do[Set[s[i], FactorInteger[i][[All, 1]]], {i, 0, nn}]; Table[Product[Times @@ Intersection[s[k], s[n]], {k, 0, n}], {n, 1, nn, 2}] (* _Michael De Vlieger_, Jul 11 2024 *)

%Y Cf. A374431, A374433.

%K nonn

%O 0,2

%A _Peter Luschny_, Jul 10 2024