A372402 Position of 2310^n among 11-smooth numbers A051038.

1, 283, 3847, 20996, 74228, 203084, 469053, 960396, 1797086, 3135610, 5173909, 8156188, 12377846, 18190320, 26005929, 36302854, 49629820, 66611231, 87951744, 114441450, 146960432, 186483973, 234087084, 290949702, 358361266, 437725888, 530566933, 638532124, 763398291, 907076258

Offset

0,2

Comments

Also position of 2310^(n+1) in A147572.

Links

Table of n, a(n) for n=0..29.

Mathematica

Table[
  Sum[Floor@ Log[11, 2310^n/(2^i*3^j*5^k*7^m)] + 1,
    {i, 0, Log[2, 2310^n]},
    {j, 0, Log[3, 2310^n/2^i]},
    {k, 0, Log[5, 2310^n/(2^i*3^j)]},
    {m, 0, Log[7, 2310^n/(2^i*3^j*5^k)]}],
  {n, 0, 8}]

Prog

(Python) # uses imports/function in A372401
print(list(islice(A372401gen(p=11), 7))) # Michael S. Branicky, Jun 05 2024
(Python)
from sympy import integer_log, prevprime
def A372402(n):
    def g(x, m): return sum((x//3**i).bit_length() for i in range(integer_log(x, 3)[0]+1)) if m==3 else sum(g(x//(m**i), prevprime(m))for i in range(integer_log(x, m)[0]+1))
    return g(2310**n, 11) # Chai Wah Wu, Sep 16 2024

Crossrefs

Cf. A022330, A051038, A147572, A372400, A372401.

Sequence in context: A142837 A064964 A381372 * A263670 A108826 A285890

Adjacent sequences: A372399 A372400 A372401 * A372403 A372404 A372405

Keyword

nonn

Author

Michael De Vlieger, Jun 03 2024

Extensions

a(14)-a(18) from Michael S. Branicky, Jun 05 2024

More terms from David A. Corneth, Jun 05 2024

Status

approved