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A163242
Row sums of A163233 and A163235.
4
0, 3, 18, 30, 90, 153, 204, 252, 492, 735, 990, 1242, 1446, 1653, 1848, 2040, 3000, 3963, 4938, 5910, 6930, 7953, 8964, 9972, 10788, 11607, 12438, 13266, 14046, 14829, 15600, 16368, 20208, 24051, 27906, 31758, 35658, 39561, 43452, 47340
OFFSET
0,2
COMMENTS
It is easily seen that these terms are always divisible by 3.
LINKS
Hsien-Kuei Hwang, Svante Janson, and Tsung-Hsi Tsai, Identities and periodic oscillations of divide-and-conquer recurrences splitting at half, arXiv:2210.10968 [cs.DS], 2022, pp. 42-43.
MATHEMATICA
Map[Total, Table[Function[k, FromDigits[#, 2] &@ Apply[Function[{a, b}, Riffle @@ Map[PadLeft[#, Max[Length /@ {a, b}]] &, {a, b}]], Map[IntegerDigits[#, 2] &@ BitXor[#, Floor[#/2]] &, {k, j}] ] ][i - j], {i, 0, 39}, {j, i, 0, -1}]] (* Michael De Vlieger, Nov 01 2022 *)
CROSSREFS
a(n) = 3*A163478(n).
Sequence in context: A169598 A202359 A118474 * A190308 A161443 A003337
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 29 2009
STATUS
approved