A286374 a(n) = A278222(n^2).

1, 2, 2, 6, 2, 12, 6, 12, 2, 30, 12, 48, 6, 210, 12, 24, 2, 30, 30, 420, 12, 360, 48, 30, 6, 120, 210, 1260, 12, 420, 24, 48, 2, 30, 30, 420, 30, 4620, 420, 480, 12, 420, 360, 1080, 48, 960, 30, 210, 6, 420, 120, 2310, 210, 3360, 1260, 1680, 12, 1260, 420, 6300, 24, 840, 48, 96, 2, 30, 30, 420, 30, 4620, 420, 2520, 30, 4620, 4620, 6720, 420, 9240, 480, 180

Offset

0,2

Links

Antti Karttunen, Table of n, a(n) for n = 0..16384

Index entries for sequences related to binary expansion of n

Formula

a(n) = A278222(A000290(n)) = A278222(n^2).

Prog

(Scheme) (define (A286374 n) (A278222 (* n n)))
(Python)
from sympy import prime, factorint
import math
def A(n): return n - 2**int(math.floor(math.log(n, 2)))
def b(n): return n + 1 if n<2 else prime(1 + (len(bin(n)[2:]) - bin(n)[2:].count("1"))) * b(A(n))
def a005940(n): return b(n - 1)
def P(n):
    f = factorint(n)
    return sorted([f[i] for i in f])
def a046523(n):
    x=1
    while True:
        if P(n) == P(x): return x
        else: x+=1
def a278222(n): return a046523(a005940(n + 1))
def a(n): return a278222(n**2) # Indranil Ghosh, May 09 2017

Crossrefs

Cf. A000290, A278222, A286243, A286375, A286376, A286377.

Cf. A159918 (one of the matched sequences).

Sequence in context: A324202 A278240 A263077 * A284012 A278243 A071223

Adjacent sequences: A286371 A286372 A286373 * A286375 A286376 A286377

Keyword

nonn,base

Author

Antti Karttunen, May 09 2017

Status

approved