OFFSET
1,5
LINKS
J. Stauduhar, Table of n, a(n) for n = 1..30
EXAMPLE
A214089(14) = 1430083494841, n#_14 = 13082761331670030, and (1430083494841^2 - 1) / (4 * 13082761331670030) = 39080794, so a(14) = 39080794.
MAPLE
PROG
(Python)
from itertools import product
from sympy import sieve, prime, isprime, primorial
from sympy.ntheory.modular import crt
def A215085(n):
return (
1
if n == 1
else (
int(
min(
filter(
isprime,
(
crt(tuple(sieve.primerange(prime(n) + 1)), t)[0]
for t in product((1, -1), repeat=n)
),
)
)
)
** 2
- 1
)
// 4
// primorial(n)
) # Chai Wah Wu, May 31 2022
for n in range(1, 16):
print(A215085(n), end=", ")
CROSSREFS
KEYWORD
nonn
AUTHOR
J. Stauduhar, Aug 02 2012
STATUS
approved