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A138618 Triangle of exponentials of Mangoldt function M(n) read by rows, in which row products give the natural numbers. 1
1, 2, 1, 3, 1, 1, 2, 2, 1, 1, 5, 1, 1, 1, 1, 1, 3, 2, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 2, 2, 1, 2, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 5, 1, 1, 2, 1, 1, 1, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 1, 2, 1, 1, 1, 1, 1, 1, 13, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Row sums are A001414. This table is similar to A139547 and A120885. Cumulative column products are A003418, A139550, A139552, A139554.

LINKS

Weisstein, Eric W., Mangoldt Function.

FORMULA

T(n,k) = if n>=k then A139547((A120885-1)) else 1.

EXAMPLE

1 = 1

2*1 = 2

3*1*1 = 3

2*2*1*1 = 4

5*1*1*1*1 = 5

1*3*2*1*1*1 = 6

7*1*1*1*1*1*1 = 7

2*2*1*2*1*1*1*1 = 8

3*1*3*1*1*1*1*1*1 = 9

1*5*1*1*2*1*1*1*1*1 = 10

11*1*1*1*1*1*1*1*1*1*1 = 11

1*1*2*3*1*2*1*1*1*1*1*1 = 12

13*1*1*1*1*1*1*1*1*1*1*1*1 = 13

PROG

(Excel cell formula) =if(mod(row(); column())=0; lookup(roundup((row()/column()); 0); A000027; A014963); 1)

CROSSREFS

Cf. A120885, A139547, A001414, A000027.

Sequence in context: A193870 A058564 A087157 * A140583 A123507 A188804

Adjacent sequences:  A138615 A138616 A138617 * A138619 A138620 A138621

KEYWORD

nonn,tabl

AUTHOR

Mats O. Granvik (mgranvik(AT)abo.fi), May 14 2008

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Last modified February 17 09:41 EST 2012. Contains 206009 sequences.