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A090324 Second in a series of triangular arrays generating the natural numbers (cf. A079946). 2
6, 13, 10, 27, 21, 18, 55, 43, 37, 34, 111, 87, 75, 69, 66, 223, 175, 151, 139, 133, 130, 447, 351, 303, 279, 267, 261, 258, 895, 703, 607, 559, 535, 523, 517, 514 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Note that for each triangular array T(row+1,col) = 2 * T(row,col) +1 and that the change from T(row,col+1) to T(row,col) can be readily discerned. In the first array that pattern is 1 2 4 8 ...while in the second, it becomes 3 6 12 24 48 ... and in general, the pattern for the k-th array will begin with 2k-1.

LINKS

Table of n, a(n) for n=1..36.

EXAMPLE

The first array begins

1

3 2

7 5 4

15 11 9 8

31 23 19 17 16

so a(1) begins with six. In general each triangular array will begin with

the next term from A079946.

CROSSREFS

Sequence in context: A070396 A130012 A265740 * A106623 A115010 A244535

Adjacent sequences:  A090321 A090322 A090323 * A090325 A090326 A090327

KEYWORD

easy,nonn,tabl

AUTHOR

Alford Arnold, Jan 26 2004

STATUS

approved

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Last modified May 21 15:02 EDT 2019. Contains 323443 sequences. (Running on oeis4.)