A052474 - OEIS

A052474

Construct difference array so that (1) first row begins with 1, (2) every row is monotonic increasing, (3) no number appears more than once, (4) smallest number not yet used begins a new row. Sequence gives main diagonal.

1, 2, 4, 7, 12, 13, 14, 15, 16, 18, 20, 21, 22, 23, 32, 35, 36, 39, 42, 48, 49, 50, 51, 53, 54, 57, 58, 59, 61, 62, 64, 66, 68, 76, 77, 78, 80, 82, 86, 87, 89, 91, 92, 93, 98, 103, 109, 110, 118, 124, 127, 128, 129, 132, 133, 135, 136, 139, 140, 141, 142, 143, 149

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..150

EXAMPLE

Array begins

1 3 9 26 73 194 ...

.2 6 17 47 121 ...

. 4 11 30 74 ...

.. 7 19 44 ...

... 12 25 ...

.... 13 ...

PROG

(Haskell)

a052474 n = a056230_tabl !! (n-1) !! 0

-- Reinhard Zumkeller, Nov 19 2011

CROSSREFS

Cf. A057153 (first row), A057154 (numbers not used), A056230 (array), A056231, A056232, A056233, A056234.

Sequence in context: A097592 A267699 A193841 * A033054 A361724 A359338

Adjacent sequences: A052471 A052472 A052473 * A052475 A052476 A052477

KEYWORD

nice,nonn,easy

AUTHOR

Jonas Wallgren, Jul 30, 2000.

STATUS

approved