A378144 a(n) = P(n) * 2^floor(log_2(prime(n+1))) = A002110(n) * A000079(A098388(n+1)).

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

Michael De Vlieger, Table of n, a(n) for n = 0..349

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

Cf. A000079, A002110, A060735, A098388, A378133.

Sequence in context: A273444 A049315 A295506 * A098224 A339123 A024049

Adjacent sequences: A378141 A378142 A378143 * A378145 A378146 A378147

Keyword

nonn,easy

Author

Michael De Vlieger, Nov 17 2024

Status

approved