A230455
Lexicographically earliest sequence of distinct positive integers such that the absolute value of the first difference contains only distinct squares.
Original entry on oeis.org
1, 2, 6, 15, 31, 56, 7, 43, 107, 26, 126, 5, 149, 318, 29, 225, 450, 9, 265, 589, 13, 374, 774, 45, 529, 1058, 34, 659, 1335, 39, 823, 1664, 64, 964, 3, 1092, 2248, 132, 1357, 2726, 22, 1466, 2987, 71, 1752, 3516, 35, 1884, 3820, 99, 2124, 4333, 108, 2412
Offset: 1
The first differences of 1, 2, 6, 15, 31,... are 1^2, 2^2, 3^2, 4^2, 5^2, 7^2, 6^2,...
A257877
Sequence (a(n)) generated by Rule 1 (in Comments) with a(1) = 0 and d(1) = 3.
Original entry on oeis.org
0, 1, 3, 2, 6, 4, 9, 5, 11, 8, 15, 10, 18, 12, 21, 14, 24, 16, 7, 19, 30, 20, 33, 22, 36, 23, 38, 26, 42, 28, 13, 31, 48, 32, 51, 34, 54, 35, 17, 39, 60, 40, 63, 41, 65, 44, 69, 46, 72, 47, 74, 50, 78, 52, 25, 55, 27, 56, 87, 58, 90, 59, 29, 62, 96, 64, 99
Offset: 1
a(1) = 0, d(1) = 3;
a(2) = 1, d(2) = 1;
a(3) = 3, d(3) = 2;
a(4) = 2, d(4) = -1.
-
a[1] = 0; d[1] = 3; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]];
s[k_] := Intersection[Range[-a[k], -1], c[k], T[k]];
Table[If[Length[s[k]] == 0, {h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}, {h = Max[s[k]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}], {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257877 *)
Table[d[k], {k, 1, zz}] (* A257915 *)
A230383
Lexicographically earliest sequence of distinct positive integers such that the first difference contains only distinct positive or negative squares.
Original entry on oeis.org
1, 2, 6, 5, 14, 10, 26, 17, 42, 78, 29, 4, 53, 37, 101, 20, 120, 56, 137, 16, 160, 60, 24, 145, 314, 25, 221, 52, 277, 21, 310, 85, 341, 197, 521, 80, 441, 41, 482, 121, 605, 76, 476, 152, 681, 105, 730, 54, 630, 146, 822, 38, 767, 142, 926, 1767, 3, 903, 62
Offset: 1
n a(n) First difference
- ---- ----------------
1 1
+1^2
2 2
+2^2
3 6
-1^2
4 5
+3^2
5 14
-2^2
6 10
+4^2
7 26
...
A257879
Sequence (a(n)) generated by Rule 1 (in Comments) with a(1) = 2 and d(1) = 0.
Original entry on oeis.org
2, 1, 3, 4, 7, 5, 9, 6, 11, 17, 13, 8, 15, 23, 16, 10, 19, 29, 21, 12, 24, 14, 25, 38, 27, 41, 28, 43, 31, 47, 33, 18, 35, 53, 37, 20, 39, 59, 40, 22, 44, 65, 45, 68, 46, 70, 49, 26, 51, 77, 52, 79, 55, 83, 57, 30, 60, 32, 61, 92, 63, 95, 64, 34, 67, 101, 69
Offset: 1
a(1) = 2, d(1) = 0;
a(2) = 1, d(2) = -1;
a(3) = 3, d(3) = 2;
a(4) = 4, d(4) = 1.
-
a[1] = 2; d[1] = 0; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]];
s[k_] := Intersection[Range[-a[k], -1], c[k], T[k]];
Table[If[Length[s[k]] == 0, {h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}, {h = Max[s[k]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}], {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257879 *)
Table[d[k], {k, 1, zz}] (* A257880 *)
A257882
Sequence (a(n)) generated by Rule 1 (in Comments) with a(1) = 2 and d(1) = 2.
Original entry on oeis.org
2, 1, 4, 5, 3, 7, 12, 9, 15, 11, 6, 13, 21, 14, 8, 17, 27, 19, 10, 22, 33, 23, 36, 25, 39, 26, 41, 29, 45, 31, 16, 34, 18, 35, 54, 37, 57, 38, 20, 42, 63, 43, 66, 44, 68, 47, 24, 49, 75, 51, 78, 53, 81, 55, 28, 58, 30, 59, 90, 61, 93, 62, 32, 65, 99, 67, 102
Offset: 1
a(1) = 2, d(1) = 2;
a(2) = 1, d(2) = -1;
a(3) = 4, d(3) = 3;
a(4) = 5, d(4) = 1.
-
a[1] = 2; d[1] = 2; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]];
s[k_] := Intersection[Range[-a[k], -1], c[k], T[k]];
Table[If[Length[s[k]] == 0, {h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}, {h = Max[s[k]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}], {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257882 *)
Table[d[k], {k, 1, zz}] (* A257918 *)
A257884
Sequence (a(n)) generated by Algorithm (in Comments) with a(1) = 0 and d(1) = 1.
Original entry on oeis.org
0, 2, 1, 4, 8, 3, 9, 5, 10, 7, 14, 6, 15, 13, 21, 11, 22, 16, 26, 12, 24, 17, 30, 18, 32, 19, 34, 23, 39, 20, 37, 28, 46, 25, 44, 27, 47, 29, 50, 35, 57, 31, 54, 38, 62, 33, 58, 36, 63, 40, 66, 41, 69, 42, 71, 43, 73, 49, 80, 45, 77, 110, 48, 82, 51, 86, 52
Offset: 1
a(1) = 0, d(1) = 1;
a(2) = 2, d(2) = 2;
a(3) = 1, d(3) = -1;
a(4) = 4, d(4) = 3.
-
a[1] = 0; d[1] = 1; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]]
Table[{h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h,
d[k + 1] = h, k = k + 1}, {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257884 *)
Table[d[k], {k, 1, zz}] (* A175499 *)
A257876
Sequence (a(n)) generated by Rule 1 (in Comments) with a(1) = 0 and d(1) = 2.
Original entry on oeis.org
0, 1, 4, 3, 7, 5, 2, 8, 13, 9, 16, 11, 19, 12, 6, 15, 25, 17, 28, 18, 30, 21, 10, 23, 37, 24, 39, 27, 43, 29, 14, 31, 49, 33, 52, 35, 55, 36, 57, 34, 56, 38, 61, 41, 20, 44, 22, 47, 73, 48, 75, 51, 79, 53, 26, 58, 87, 59, 89, 60, 91, 54, 88, 50, 83, 42, 77
Offset: 1
a(1) = 0, d(1) = 2;
a(2) = 1, d(2) = 1;
a(3) = 3, d(3) = 3;
a(4) = 4, d(4) = -1.
The first terms of (d(n)) are (2,1,3,-1,4,-2,-3,6,5,...), which differs from A131389 only in initial terms.
-
a[1] = 0; d[1] = 2; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]];
s[k_] := Intersection[Range[-a[k], -1], c[k], T[k]];
Table[If[Length[s[k]] == 0, {h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}, {h = Max[s[k]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}], {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257876 *)
Table[d[k], {k, 1, zz}] (* A131389 essentially *)
A257878
Sequence (a(n)) generated by Rule 1 (in Comments) with a(1) = 1 and d(1) = 1.
Original entry on oeis.org
1, 3, 2, 5, 9, 7, 4, 10, 6, 11, 18, 13, 21, 15, 8, 17, 27, 19, 30, 20, 32, 23, 12, 25, 39, 26, 14, 29, 45, 31, 16, 33, 51, 35, 54, 37, 57, 38, 59, 41, 63, 43, 22, 46, 24, 47, 72, 49, 75, 50, 77, 53, 81, 55, 28, 58, 87, 56, 88, 60, 91, 62, 95, 65, 99, 67, 34
Offset: 1
a(1) = 1, d(1) = 1;
a(2) = 3, d(2) = 2;
a(3) = 2, d(3) = -1;
a(4) = 5, d(4) = -3.
-
a[1] = 1; d[1] = 1; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]];
s[k_] := Intersection[Range[-a[k], -1], c[k], T[k]];
Table[If[Length[s[k]] == 0, {h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}, {h = Max[s[k]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}], {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257878 *)
Table[d[k], {k, 1, zz}] (* A131389 essentially *)
A257881
Sequence (a(n)) generated by Rule 1 (in Comments) with a(1) = 2 and d(1) = 1.
Original entry on oeis.org
2, 1, 3, 6, 4, 8, 5, 10, 16, 12, 7, 14, 22, 15, 9, 18, 28, 20, 11, 23, 13, 24, 37, 26, 40, 27, 42, 30, 46, 32, 17, 34, 52, 36, 19, 38, 58, 39, 21, 43, 64, 44, 67, 45, 69, 48, 25, 50, 76, 51, 78, 54, 82, 56, 29, 59, 31, 60, 91, 62, 94, 63, 33, 66, 100, 68, 35
Offset: 1
a(1) = 2, d(1) = 0;
a(2) = 1, d(2) = -1;
a(3) = 3, d(3) = 2;
a(4) = 6, d(4) = 3.
-
a[1] = 2; d[1] = 1; k = 1; z = 10000; zz = 120;
A[k_] := Table[a[i], {i, 1, k}]; diff[k_] := Table[d[i], {i, 1, k}];
c[k_] := Complement[Range[-z, z], diff[k]];
T[k_] := -a[k] + Complement[Range[z], A[k]];
s[k_] := Intersection[Range[-a[k], -1], c[k], T[k]];
Table[If[Length[s[k]] == 0, {h = Min[Intersection[c[k], T[k]]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}, {h = Max[s[k]], a[k + 1] = a[k] + h, d[k + 1] = h, k = k + 1}], {i, 1, zz}];
u = Table[a[k], {k, 1, zz}] (* A257881 *)
Table[d[k], {k, 1, zz}] (* essentially A257880 *)
A327844
Table read by antidiagonals: the m-th row gives the sequence constructed by repeatedly choosing the smallest positive number not already in the row such that for each k = 1, ..., m, the k-th differences are distinct.
Original entry on oeis.org
1, 1, 2, 1, 2, 4, 1, 2, 4, 3, 1, 2, 4, 3, 6, 1, 2, 4, 3, 6, 10, 1, 2, 4, 3, 6, 11, 5, 1, 2, 4, 3, 6, 11, 5, 11, 1, 2, 4, 3, 6, 11, 5, 9, 7, 1, 2, 4, 3, 6, 11, 5, 9, 7, 12, 1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 9, 1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 10, 16, 1, 2, 4, 3
Offset: 1
Table begins:
1, 2, 4, 3, 6, 10, 5, 11, 7, 12, 9, 16, 8, 17, 15, 23, ...
1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 10, 18, 8, 15, 25, 12, ...
1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 10, 18, 8, 15, 25, 12, ...
1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 10, 18, 8, 15, 27, 12, ...
1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 10, 18, 8, 15, 27, 12, ...
1, 2, 4, 3, 6, 11, 5, 9, 7, 13, 10, 18, 8, 15, 27, 14, ...
Comments