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A378144
a(n) = P(n) * 2^floor(log_2(prime(n+1))) = A002110(n) * A000079(A098388(n+1)).
2
1, 4, 24, 120, 1680, 18480, 480480, 8168160, 155195040, 3569485920, 103515091680, 6417935684160, 237463620313920, 9736008432870720, 418648362613440960, 19676473042831725120, 1042853071270081431360, 61528331204934804450240, 7506456407002046142929280, 502932579269137091576261760
OFFSET
0,2
COMMENTS
Last term in row n of A378133.
a(n) is the largest product of a power of 2 and A002110(n) less than A002110(n+1).
LINKS
FORMULA
a(n) = A002110(n)*A000079(A098388(n+1)).
MATHEMATICA
{1}~Join~Table[Product[Prime[i], {i, n}]*2^Floor[Log2[Prime[n + 1]]], {n, 120}]
PROG
(Python)
from sympy import primorial, prime
def A378144(n): return primorial(n)<<prime(n+1).bit_length()-1 if n else 1 # Chai Wah Wu, Nov 19 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michael De Vlieger, Nov 17 2024
STATUS
approved