A377419
Minimum sum of a maximal subset of {1..n} such that every pair of distinct elements has a different difference.
Original entry on oeis.org
0, 1, 3, 3, 5, 7, 7, 7, 10, 10, 13, 15, 15, 15, 17, 17, 19, 19, 23, 24, 28, 29, 30, 30, 33, 34, 35, 36, 41, 41, 46, 48, 50, 52, 52, 53, 56, 56, 59, 59, 61, 63, 65, 68, 71, 71, 75, 81, 83, 84, 86, 87, 88, 89, 90, 91, 92, 93, 95, 95, 98, 98, 98, 105, 112, 118, 121, 121, 124
Offset: 0
a(0) = 0 = sum of {}.
a(1) = 1 = sum of {1}.
a(2) = 3 = sum of {1,2}.
a(3) = 3 = sum of {1,2}.
a(4) = 5 = sum of {2,3}.
a(5) = 7 = sum of {1,2,4}.
a(12) = 15 = sum of {1,2,5,7} or {1,2,4,8}.
a(20) = 28 = sum of {2,5,10,11} or {1,2,4,8,13}.
See also the examples in A325879.
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a(n)={
my(ismaxl(b,w)=for(k=1, n, if(!bittest(b,k) && !bitand(w,bitor(b,1< n, if(ismaxl(b,w),0,n^2),
my(s=self()(k+1, b,w));
b+=1<
A382395
Number of maximum sized subsets of {1..n} such that every pair of distinct elements has a different difference.
Original entry on oeis.org
1, 1, 1, 3, 2, 6, 14, 2, 10, 26, 60, 110, 4, 22, 68, 156, 320, 584, 8, 24, 80, 206, 504, 1004, 1910, 3380, 10, 34, 98, 282, 760, 1618, 3334, 6360, 11482, 2, 22, 70, 214, 540, 1250, 2718, 5712, 10910, 20418, 2, 12, 30, 90, 230, 562, 1228, 2690, 5550, 11260, 21164, 2, 4, 6, 10, 18
Offset: 0
The a(0) = 1 set is {}.
The a(1) = 1 set is {1}.
The a(2) = 1 set is {1,2}.
The a(3) = 3 sets: {1,2}, {1,3}, {2,3}.
The a(4) = 2 sets: {1,2,4}, {1,3,4}.
The a(5) = 6 sets: {1,2,4}, {1,2,5}, {1,3,4}, {1,4,5}, {2,3,5}, {2,4,5}.
The a(6) = 14 sets: {1,2,4}, {1,2,5}, {1,2,6}, {1,3,4}, {1,3,6}, {1,4,5}, {1,4,6}, {1,5,6}, {2,3,5}, {2,3,6}, {2,4,5}, {2,5,6}, {3,4,6}, {3,5,6}.
The a(7) = 2 sets: {1,2,5,7}, {1,3,6,7}.
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a(n)={
local(best,count);
my(recurse(k,r,b,w)=
if(k > n, if(r>=best, if(r>best,best=r;count=0); count++),
self()(k+1, r, b, w);
b+=1<
Showing 1-2 of 2 results.
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