%I #11 Aug 06 2023 17:50:09
%S 1,1,2,2,4,4,9,11,24,38,75,131,263,476,928,1750,3386,6439,12455,23853,
%T 46097,88709,171471,330939,640472,1238755,2400154,4650857,9022792,
%U 17510820,34015138,66106492,128571563,250191929,487175381,949133736,1850223956,3608650389
%N Number of subsets of {1..n} containing n and all first differences.
%H Rémy Sigrist, <a href="/A364752/a364752.txt">C++ program</a>
%e The a(1) = 1 through a(6) = 9 subsets:
%e {1} {2} {3} {4} {5} {6}
%e {1,2} {1,2,3} {2,4} {1,2,3,5} {3,6}
%e {1,2,4} {1,2,4,5} {2,4,6}
%e {1,2,3,4} {1,2,3,4,5} {1,2,3,6}
%e {1,2,4,6}
%e {1,2,3,4,6}
%e {1,2,3,5,6}
%e {1,2,4,5,6}
%e {1,2,3,4,5,6}
%t Table[If[n==0,1,Length[Select[Subsets[Range[n]], MemberQ[#,n]&&SubsetQ[#,Differences[#]]&]]],{n,0,10}]
%Y Partial sums are A364671, complement A364672.
%Y The complement is counted by A364753.
%Y A054519 counts subsets containing differences, A326083 containing sums.
%Y A364463 counts subsets disjoint from differences, complement A364466.
%Y A364673 counts partitions containing differences, A364674, A364675.
%Y Cf. A151897, A196723, A237668, A325325, A363225, A364345, A364464, A364537.
%K nonn
%O 0,3
%A _Gus Wiseman_, Aug 06 2023
%E More terms from _Rémy Sigrist_, Aug 06 2023