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A066205
a(n) = Product_{k=1..n} prime(2k-1), where prime(k) is k-th prime.
28
2, 10, 110, 1870, 43010, 1333310, 54665710, 2569288370, 151588013830, 10156396926610, 741416975642530, 61537608978329990, 5969148070898009030, 614822251302494930090, 67015625391971947379810, 8510984424780437317235870, 1166004866194919912461314190
OFFSET
1,1
COMMENTS
Equivalently, a(n) is the product of the first n odd-indexed primes. - Jon E. Schoenfield, Jan 12 2022
LINKS
EXAMPLE
a(3) = prime(1) * prime(3) * prime(5) = 2 * 5 * 11 = 110.
MAPLE
a:= proc(n) option remember;
`if`(n=0, 1, a(n-1)*ithprime(2*n-1))
end:
seq(a(n), n=1..17); # Alois P. Heinz, Jan 12 2022
MATHEMATICA
FoldList[Times, Array[Prime[2 # - 1] &, 17]] (* Michael De Vlieger, Jan 12 2022 *)
PROG
(PARI) { for (n=1, 100, p=1; for (k=1, n, p*=prime(2*k - 1)); write("b066205.txt", n, " ", p) ) } \\ Harry J. Smith, Feb 05 2010
(PARI) a(n) = prod(k=1, n, prime(2*k-1)); \\ Michel Marcus, Jan 13 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Dec 16 2001
STATUS
approved