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A361189
Infinite sequence of nonzero integers build the greedy way such that the sums Sum_{i = k*2^e..(k+1)*2^e} a(i) with k, e >= 0 are all distinct; each term is minimal in absolute value and in case of a tie, preference is given to the positive value.
2
1, 2, -1, -4, -3, -6, 4, -11, 5, 6, 7, 8, -8, -12, 9, 21, -10, -13, 12, 25, 13, 16, -14, 31, -15, -17, 19, 33, -19, -21, 22, 41, -22, -24, 24, 49, -25, -26, -27, -28, 28, 34, -29, 61, -30, -31, -33, -34, 35, 39, -35, 75, -36, -37, 38, 77, -38, -39, -41, -42
OFFSET
1,2
COMMENTS
This sequence is a variant of A361144 where we allows negative values.
In order for the sequence to be infinite, zero sums are forbidden.
We can arrange the terms of the sequence as the leaves of a perfect infinite binary tree, the sums with e > 0 corresponding to parent nodes; each node will contain a different value and all nonzero values will appear in the tree.
LINKS
Rémy Sigrist, C++ program
EXAMPLE
The first terms (at the bottom of the tree) alongside the corresponding sums are:
18
---------------------------------
-18 36
----------------- -----------------
-2 -16 26 10
--------- --------- --------- ---------
3 -5 -9 -7 11 15 -20 30
----- ----- ----- ----- ----- ----- ----- -----
1 2 -1 -4 -3 -6 4 -11 5 6 7 8 -8 -12 9 21
PROG
(C++) See Links section.
CROSSREFS
Cf. A361144.
Sequence in context: A347082 A186421 A351752 * A004560 A345668 A076981
KEYWORD
sign
AUTHOR
Rémy Sigrist, Mar 03 2023
STATUS
approved