A360435 -id:A360435 - cp's OEIS frontend

A369059 a(0) = 0, and for n > 0, a(n) is the square of the product of first n-1 odd primes.

0, 1, 9, 225, 11025, 1334025, 225450225, 65155115025, 23520996524025, 12442607161209225, 10464232622576958225, 10056127550296456854225, 13766838616355849433434025, 23142055714094182897602596025, 42789661015360144177667200050225, 94522361182930558488466844910947025, 265513312562851938794103367354850193225

Offset: 0

Antti Karttunen, Jan 19 2024

nonn

Terms a(2) .. a(9) are equal to the terms A360435(1..8).

Index entries for sequences related to primorial numbers

Cf. A000005, A000244, A002110, A002620, A061742, A070826, A360435.

An upper bound for A368704, and also for A360435(n-1).

Join[{0}, FoldList[Times, 1, Prime[Range[2, 16]]^2]] (* Amiram Eldar, Jan 19 2024 *)

A002110(n) = prod(i=1,n,prime(i));
A002620(n) = ((n^2)>>2);
A369059(n) = A002620(A002110(n));

a(n) = A002620(A002110(n)).
For n > 0, a(n) = A061742(n)/4 = A070826(n)^2.
For n > 0, a(n) >= A368704(n) and for n > 1, a(n) >= A360435(n-1).
For n > 0, A000005(a(n)) = A000244(n-1) = 3^(n-1).

cp's OEIS Frontend

A369059 a(0) = 0, and for n > 0, a(n) is the square of the product of first n-1 odd primes.

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