OFFSET
1,3
COMMENTS
In other words, a(n) is the number of strict integer partitions of n with distinct first differences. - Gus Wiseman, Mar 25 2021
LINKS
Fausto A. C. Cariboni, Table of n, a(n) for n = 1..500 (terms 1..100 from Seiichi Manyama)
EXAMPLE
n = 9
[9] ooooooooo
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[8, 1] *******o a_1 - a_2 = 7.
oooooooo
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[7, 2] *****oo a_1 - a_2 = 5.
ooooooo
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[6, 3] ***ooo a_1 - a_2 = 3.
oooooo
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[6, 2, 1] *o a_2 - a_3 = 1.
****oo a_1 - a_2 = 4.
oooooo
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[5, 4] *oooo a_1 - a_2 = 1.
ooooo
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a(9) = 6.
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&UnsameQ@@Differences[#]&]], {n, 0, 30}] (* Gus Wiseman, Mar 27 2021 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 11 2018
STATUS
approved