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A249153
Exponent of 2 in the hyperfactorial of 2n: a(n) = A007814(A002109(2n)).
4
0, 2, 10, 16, 40, 50, 74, 88, 152, 170, 210, 232, 304, 330, 386, 416, 576, 610, 682, 720, 840, 882, 970, 1016, 1208, 1258, 1362, 1416, 1584, 1642, 1762, 1824, 2208, 2274, 2410, 2480, 2696, 2770, 2922, 3000, 3320, 3402, 3570, 3656, 3920, 4010, 4194, 4288, 4768, 4866, 5066, 5168, 5480, 5586, 5802, 5912
OFFSET
0,2
FORMULA
a(n) = A249152(2*n) = A007814(A002109(2*n)).
a(n) = 2*A143157(n).
a(n) ~ 2*n^2. - Amiram Eldar, Sep 10 2024
MATHEMATICA
Table[IntegerExponent[Hyperfactorial[2*n], 2], {n, 0, 55}] (* Amiram Eldar, Sep 10 2024 *)
PROG
(Scheme, two alternative versions)
(define (A249153 n) (* 2 (A143157 n)))
(define (A249153 n) (A249152 (+ n n)))
(Python)
from sympy import multiplicity
A249153_list, n = [0], 0
for i in range(2, 20002, 2):
n += multiplicity(2, i)*i
A249153_list.append(n) # Chai Wah Wu, Aug 21 2015
CROSSREFS
Bisection of A249152.
Cf. A002109, A007814, A143157, A069895 (first differences).
Sequence in context: A110761 A046036 A131474 * A276046 A268481 A009387
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 25 2014
STATUS
approved