OFFSET
1,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..2^11
FORMULA
a(2^n) = 2^A000325(n) for n>0 (conjectured).
EXAMPLE
Solutions for n = 7:
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1 +3 +6 +10 +15 +21 +28 = 84.
1 +3 +6 +10 +15 +21 -28 = 28.
1 +3 +6 +10 +15 -21 +28 = 42.
1 +3 +6 +10 +15 -21 -28 = -14.
1 +3 -6 +10 -15 +21 +28 = 42.
1 +3 -6 +10 -15 +21 -28 = -14.
1 +3 -6 +10 -15 -21 +28 = 0.
1 +3 -6 +10 -15 -21 -28 = -56.
1 -3 +6 -10 -15 +21 +28 = 28.
1 -3 +6 -10 -15 +21 -28 = -28.
1 -3 +6 -10 -15 -21 +28 = -14.
1 -3 +6 -10 -15 -21 -28 = -70.
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 02 2018
STATUS
approved