A062410 Square spiral sequence: numbers are placed in a square spiral, a(1)=1, a(n) is found as the sum of the row (in the previous direction) a(n-1) is in.

1, 1, 2, 3, 4, 9, 11, 24, 28, 31, 94, 105, 114, 344, 375, 403, 427, 1663, 1777, 1882, 1976, 7725, 8152, 8555, 8930, 9274, 44612, 46588, 48470, 50247, 51910, 251101, 260375, 269305, 277860, 286012, 293737, 1690300, 1742210, 1792457, 1840927

Offset

1,3

Links

Table of n, a(n) for n=1..41.

F. M. van Lamoen, Spiral recurrence.

Example

The initial part of the square spiral sequence is
.
         344-114
               |
   4---3---2 105
   |       |   |
   9   1---1  94
   |           |
  11--24--28--31

Crossrefs

Cf. A063177, A063178.

Sequence in context: A217493 A368349 A125774 * A145772 A027866 A283596

Adjacent sequences: A062407 A062408 A062409 * A062411 A062412 A062413

Keyword

nonn

Author

Floor van Lamoen, Jul 09 2001

Status

approved