A374730 a(n) = n * binomial(floor(log_2(n)) + 1, 2).
0, 0, 2, 3, 12, 15, 18, 21, 48, 54, 60, 66, 72, 78, 84, 90, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 480, 495, 510, 525, 540, 555, 570, 585, 600, 615, 630, 645, 660, 675, 690, 705, 720, 735, 750, 765, 780, 795, 810, 825, 840
Offset: 0
Keywords
Programs
-
Maple
a := n -> n * binomial(ilog2(n) + 1, 2): seq(a(n), n = 0..56); # Peter Luschny, Jul 19 2024
-
Mathematica
Table[n * Binomial[BitLength[n], 2], {n, 0, 60}] (* Amiram Eldar, Jul 23 2024 *) -
PARI
a(n) = n * binomial(logint(n, 2) + 1, 2); \\ Michel Marcus, Jul 23 2024
-
Python
def a(n): q = n.bit_length() - 1 return n * q * (q + 1) >> 1 print([a(n) for n in range(61)])