A183534
Square array of generalized Ulam numbers U(n,k), n>=1, k>=2, read by antidiagonals: U(n,k) = n if n<=k; for n>k, U(n,k) = least number > U(n-1,k) which is a unique sum of k distinct terms U(i,k) with i
1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 6, 6, 1, 2, 3, 4, 9, 8, 1, 2, 3, 4, 10, 10, 11, 1, 2, 3, 4, 5, 16, 11, 13, 1, 2, 3, 4, 5, 15, 17, 12, 16, 1, 2, 3, 4, 5, 6, 25, 18, 28, 18, 1, 2, 3, 4, 5, 6, 21, 26, 19, 29, 26, 1, 2, 3, 4, 5, 6, 7, 36, 27, 22, 30, 28, 1, 2, 3, 4, 5, 6, 7, 28, 37, 28, 64, 53, 36
Offset: 1
A183527 An Ulam-type sequence: a(n) = n if n<=4; for n>4, a(n) = least number > a(n-1) which is a unique sum of 4 distinct earlier terms.
1, 2, 3, 4, 10, 16, 17, 18, 19, 22, 64, 65, 66, 68, 69, 128, 132, 188, 190, 191, 194, 252, 253, 255, 313, 314, 318, 374, 376, 377, 436, 441, 496, 497, 499, 500, 502, 560, 561, 563, 621, 622, 626, 682, 684, 685, 687, 745, 746, 805, 811
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(5) = 10 = 1 + 2 + 3 + 4 = 4*5/2, because it is the least number >4 with a unique sum of 4 distinct earlier terms. a(6) = 16 = 1 + 2 + 3 + 10 = 4^2, because it is the least number >10 with a unique sum of 4 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..1000
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
Formula
Conjectured G.f.: (-61*x^124-56*x^118+53*x^117+3*x^116 -x^115+2*x^114-65*x^113-58*x^112+57*x^111 -56*x^110-x^109-57*x^108+54*x^106 +3*x^105+58*x^104-52*x^102+50*x^101-55*x^100 +56*x^95-53*x^94-3*x^93+x^92-2*x^91 +2*x^90+x^87-x^86 +41*x^84-51*x^83-66*x^82-58*x^81 -52*x^79+4*x^78-58*x^77 -x^74-x^73-x^72-54*x^71 -6*x^70-59*x^69-x^68-58*x^67-2*x^66 -x^65-2*x^64-56*x^63-4*x^62-x^61 -58*x^60-2*x^59-59*x^58-x^57-x^56 -2*x^55-x^54-x^53-54*x^52-6*x^51 -59*x^50-x^49-58*x^48-2*x^47-x^46 -2*x^45-56*x^44-4*x^43-x^42-58*x^41 -2*x^40-x^39-58*x^38-2*x^37-x^36 -2*x^35-x^34-55*x^33-5*x^32-59*x^31 -x^30-2*x^29-56*x^28-4*x^27-x^26 -58*x^25-2*x^24-x^23-58*x^22-3*x^21 -x^20-2*x^19-56*x^18-4*x^17-59*x^16 -x^15-2*x^14-x^13-x^12-42*x^11 -3*x^10-x^9-x^8-x^7-6*x^6 -6*x^5-x^4-x^3-x^2-x) / (-x^74+x^73+x-1). (This has been verified for n up to 1000.)
A183533 An Ulam-type sequence: a(n) = n if n<=10; for n>10, a(n) = least number > a(n-1) which is a unique sum of 10 distinct earlier terms.
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 55, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 145, 163, 190, 217, 235, 271, 280, 1740, 1741, 1744, 1745, 1799, 1804, 1805, 1824, 1825, 1831, 1859, 1869, 1913, 1914, 3554, 10521, 10522, 10526, 10527, 10537, 10563, 10564
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(11) = 55 = 1 + ... + 10 = 10*11/2, because it is the least number >10 with a unique sum of 10 distinct earlier terms. a(12) = 100 = 1 + ... + 9 + 55 = 10^2, because it is the least number >55 with a unique sum of 10 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..120
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
A183532 An Ulam-type sequence: a(n) = n if n<=9; for n>9, a(n) = least number > a(n-1) which is a unique sum of 9 distinct earlier terms.
1, 2, 3, 4, 5, 6, 7, 8, 9, 45, 81, 82, 83, 84, 85, 86, 87, 88, 89, 117, 133, 153, 177, 189, 221, 225, 1325, 1326, 1328, 1329, 1373, 1378, 1379, 1391, 1392, 1398, 1423, 1427, 2717, 2718, 4031, 4032, 4035, 4037, 4039, 5316, 5319, 5346, 5352, 5353, 5354, 5361
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(10) = 45 = 1 + ... + 9 = 9*10/2, because it is the least number >9 with a unique sum of 9 distinct earlier terms. a(11) = 81 = 1 + ... + 8 + 45 = 9^2, because it is the least number >45 with a unique sum of 9 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..200
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
A183528 An Ulam-type sequence: a(n) = n if n<=5; for n>5, a(n) = least number > a(n-1) which is a unique sum of 5 distinct earlier terms.
1, 2, 3, 4, 5, 15, 25, 26, 27, 28, 29, 35, 43, 45, 165, 171, 172, 174, 180, 181, 328, 333, 338, 339, 340, 341, 493, 499, 500, 647, 652, 657, 658, 659, 660, 661, 662, 663, 815, 818, 819, 971, 1127, 1137, 1138, 1139, 1140, 1141, 1142
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(6) = 15 = 1 + 2 + 3 + 4 + 5 = 5*6/2, because it is the least number >5 with a unique sum of 5 distinct earlier terms. a(7) = 25 = 1 + 2 + 3 + 4 + 15 = 5^2, because it is the least number >15 with a unique sum of 5 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..1000
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
A183529 An Ulam-type sequence: a(n) = n if n<=6; for n>6, a(n) = least number > a(n-1) which is a unique sum of 6 distinct earlier terms.
1, 2, 3, 4, 5, 6, 21, 36, 37, 38, 39, 40, 41, 51, 61, 66, 284, 285, 289, 290, 297, 298, 299, 310, 312, 559, 561, 562, 570, 571, 574, 575, 834, 836, 837, 838, 839, 840, 841, 849, 850, 1109, 1124, 1125, 1126, 1127, 1386, 1401, 1402, 1661, 1676, 1677, 1936, 1951
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(7) = 21 = 1 + ... + 6 = 6*7/2, because it is the least number >6 with a unique sum of 6 distinct earlier terms. a(8) = 36 = 1 + ... + 5 + 21 = 6^2, because it is the least number >21 with a unique sum of 6 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..700
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
A183530 An Ulam-type sequence: a(n) = n if n<=7; for n>7, a(n) = least number > a(n-1) which is a unique sum of 7 distinct earlier terms.
1, 2, 3, 4, 5, 6, 7, 28, 49, 50, 51, 52, 53, 54, 55, 70, 82, 91, 109, 112, 555, 556, 563, 564, 572, 573, 576, 583, 584, 591, 593, 1103, 1104, 1105, 1111, 1112, 1124, 1632, 1637, 1642, 1643, 1648, 1653, 1654, 1655, 1656, 1657, 1660, 1661, 1662, 1671, 1672, 2184
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(8) = 28 = 1 + ... + 7 = 7*8/2, because it is the least number >7 with a unique sum of 7 distinct earlier terms. a(9) = 49 = 1 + ... + 6 + 28 = 7^2, because it is the least number >28 with a unique sum of 7 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..500
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
A183531 An Ulam-type sequence: a(n) = n if n<=8; for n>8, a(n) = least number > a(n-1) which is a unique sum of 8 distinct earlier terms.
1, 2, 3, 4, 5, 6, 7, 8, 36, 64, 65, 66, 67, 68, 69, 70, 71, 92, 106, 120, 141, 148, 792, 793, 802, 803, 816, 817, 820, 828, 830, 838, 844, 1591, 1592, 1606, 1607, 2356, 2357, 2358, 2359, 2360, 2384, 2395, 2402, 3149, 3150, 3169, 3919, 3920, 3921, 3922, 3923
Offset: 1
Keywords
Comments
An Ulam-type sequence - see A002858 for further information.
Examples
a(9) = 36 = 1 + ... + 8 = 8*9/2, because it is the least number >8 with a unique sum of 8 distinct earlier terms. a(10) = 64 = 1 + ... + 7 + 36 = 8^2, because it is the least number >36 with a unique sum of 8 distinct earlier terms.
Links
- Alois P. Heinz, Table of n, a(n) for n = 1..500
- Index entries for Ulam numbers
Programs
-
Maple
# see A183534 for programs.
Comments
Examples
Links
Crossrefs
Programs
Maple
Mathematica
PARI