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Sum over all partitions of n of the bitwise XOR of the parts.
6

%I #16 Mar 19 2019 04:34:45

%S 0,1,2,7,8,19,26,61,70,126,146,270,308,519,604,1054,1222,1929,2208,

%T 3454,3930,5862,6576,9833,11102,16052,17904,25752,28764,40479,44830,

%U 62988,70188,97151,107662,148141,164710,223783,247380,334035,370406,495313,547000

%N Sum over all partitions of n of the bitwise XOR of the parts.

%H Alois P. Heinz, <a href="/A306903/b306903.txt">Table of n, a(n) for n = 0..1000</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Bitwise operation">Bitwise operation</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Commutative_property">Commutative property</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Identity_element">Identity element</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Partition_(number_theory)">Partition (number theory)</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Truth_table">Truth table</a>

%F a(n) is odd <=> n in { A067567 }.

%p b:= proc(n, i, r) option remember; `if`(i<1, 0, (t->

%p `if`(i<n, b(n-i, min(i, n-i), t), 0)+

%p `if`(i=n, t, 0)+b(n, i-1, r))(Bits[Xor](i, r)))

%p end:

%p a:= n-> b(n$2, 0):

%p seq(a(n), n=0..45);

%Y Cf. A006906, A066186, A067567, A306884, A306895, A306901, A306902, A306925.

%K nonn,base

%O 0,3

%A _Alois P. Heinz_, Mar 15 2019