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A145605 Irregular triangle in which row n consists of all numbers x such that x and x+1 are both prime(n)-smooth numbers but not both prime(n-1)-smooth. 4
1, 2, 3, 8, 4, 5, 9, 15, 24, 80, 6, 7, 14, 20, 27, 35, 48, 49, 63, 125, 224, 2400, 4374, 10, 11, 21, 32, 44, 54, 55, 98, 99, 120, 175, 242, 384, 440, 539, 3024, 9800, 12, 13, 25, 26, 39, 64, 65, 77, 90, 104, 143, 168, 195, 324, 350, 351, 363, 624, 675, 728, 1000, 1715 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

The length of row n is A145604(n). The largest x in row n is A145606(n). This is sequence A138180 with only the first occurrence of each number retained. Row n begins with prime(n)-1.

LINKS

T. D. Noe, Rows n=1..15 of triangle, flattened

EXAMPLE

1

2, 3, 8

4, 5, 9, 15, 24, 80

6, 7, 14, 20, 27, 35, 48, 49, 63, 125, 224, 2400, 4374

CROSSREFS

Sequence in context: A079555 A100870 A195794 * A111809 A100869 A110142

Adjacent sequences:  A145602 A145603 A145604 * A145606 A145607 A145608

KEYWORD

nonn,tabf

AUTHOR

T. D. Noe (noe(AT)sspectra.com), Oct 14 2008, Nov 03 2008

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Last modified February 13 21:09 EST 2012. Contains 205561 sequences.