A124301 Smallest number m such that A124300(m) >= n.

1, 2, 29, 242, 844, 22020, 217070, 1092747, 8870024, 221167422, 221167422

Offset

0,2

Comments

A008683(a(n) + k) = A008683(a(n)) for 0<=k<=n.

Links

Table of n, a(n) for n=0..10.

Example

a(4) = 844:
mu(844) = mu(2*2*211) = 0;
mu(844+1) = mu(5*13*13) = 0;
mu(844+2) = mu(2*3*3*47) = 0;
mu(844+3) = mu(7*11*11) = 0;
mu(844+4) = mu(2*2*2*2*53) = 0.

Prog

(PARI) a(n)={x=1; k=moebius(x); y=n+x; while(x<y, x++; if(moebius(x)!=k, k=moebius(x); y=x+n)); x-n} \\ Jinyuan Wang, Apr 06 2019
(Python)
from itertools import count
from sympy import mobius
def A124301(n):
    c, m = 1, 1
    for i in count(2):
        k = mobius(i)
        if m!=k:
            if c>n:
                return i-c
            c = 0
        c += 1
        m = k # Chai Wah Wu, Oct 08 2024

Crossrefs

Cf. A008683 (Möbius function mu), A124300.

Sequence in context: A036939 A342962 A342971 * A276196 A077023 A352065

Adjacent sequences: A124298 A124299 A124300 * A124302 A124303 A124304

Keyword

nonn,more

Author

Reinhard Zumkeller, Oct 25 2006

Extensions

a(7)-a(8) from Peter T. Wang (peterw(AT)ugcs.caltech.edu), Feb 04 2007

Name edited by and a(9)-a(10) from Jinyuan Wang, Apr 06 2019

Status

approved