A174843 - OEIS

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A174843

Irregular triangle in which row n lists the divisors of prime(n)-1.

1, 1, 2, 1, 2, 4, 1, 2, 3, 6, 1, 2, 5, 10, 1, 2, 3, 4, 6, 12, 1, 2, 4, 8, 16, 1, 2, 3, 6, 9, 18, 1, 2, 11, 22, 1, 2, 4, 7, 14, 28, 1, 2, 3, 5, 6, 10, 15, 30, 1, 2, 3, 4, 6, 9, 12, 18, 36, 1, 2, 4, 5, 8, 10, 20, 40, 1, 2, 3, 6, 7, 14, 21, 42, 1, 2, 23, 46, 1, 2, 4, 13, 26, 52, 1, 2, 29, 58, 1, 2, 3, 4

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

OFFSET

1,3

COMMENTS

Row n begins with 1, ends with prime(n)-1, and has A008328(n) terms.

LINKS

T. D. Noe, Rows n=1..500 of triangle, flattened

MATHEMATICA

Flatten[Table[Divisors[p-1], {p, Prime[Range[100]]}]]

CROSSREFS

Sequence in context: A356184 A292477 A081532 * A253572 A141539 A340547

Adjacent sequences: A174840 A174841 A174842 * A174844 A174845 A174846

KEYWORD

nonn,tabf

AUTHOR

T. D. Noe, Mar 30 2010

STATUS

approved