A037260 a()=A037260 and its first [ A037261 ], 2nd [ A037262 ] and 3rd [ A037263 ] differences together include every number at most once and are monotonic and minimal.

1, 3, 9, 26, 62, 127, 233, 393, 621, 932, 1342, 1869, 2533, 3355, 4357, 5562, 6994, 8678, 10641, 12911, 15518, 18493, 21868, 25676, 29951, 34728, 40044, 45937, 52446, 59611, 67474, 76078, 85467, 95686, 106781, 118799, 131788, 145797

Offset

0,2

Comments

5 is the only number less than 100 not used in any of the 4 sequences - Larry Reeves (larryr(AT)acm.org), Sep 25 2000

Links

Table of n, a(n) for n=0..37.

Example

After 1 3 9 26 62
------ 2 6 17 36
------- 4 11 19
-------- 7 8
the next free number is 10 which we CAN add to 4th row.

Crossrefs

A037260-A037263 are 4-rowed analog of A037257-A037259. See A005228, A030124 for 2-rowed version.

Sequence in context: A370642 A358915 A218916 * A035313 A055293 A034531

Adjacent sequences: A037257 A037258 A037259 * A037261 A037262 A037263

Keyword

nonn,easy

Author

N. J. A. Sloane

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Sep 25 2000

Status

approved