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A138143 Triangle read by rows in which row n lists p(1), p(2), ..., p(n), p(n-1), ..., p(1), where p(i) = i-th prime. 2
2, 2, 3, 2, 2, 3, 5, 3, 2, 2, 3, 5, 7, 5, 3, 2, 2, 3, 5, 7, 11, 7, 5, 3, 2, 2, 3, 5, 7, 11, 13, 11, 7, 5, 3, 2, 2, 3, 5, 7, 11, 13, 17, 13, 11, 7, 5, 3, 2, 2, 3, 5, 7, 11, 13, 17, 19, 17, 13, 11, 7, 5, 3, 2, 2, 3, 5, 7, 11, 13, 17, 19, 23, 19, 17, 13, 11, 7, 5, 3, 2, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 23, 19, 17, 13, 11, 7, 5, 3, 2 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Row n contains 2n-1 terms and each column lists the prime numbers A000040.

Triangle of primes mentioned in A061802.

EXAMPLE

Triangle begins:

.............. 2

........... 2, 3, 2

........ 2, 3, 5, 3, 2

..... 2, 3, 5, 7, 5, 3, 2

.. 2, 3, 5, 7,11, 7, 5, 3, 2

CROSSREFS

Cf. A000040, A061802, A066622, A037126.

Sequence in context: A153095 A054483 A108939 * A106441 A131836 A133829

Adjacent sequences:  A138140 A138141 A138142 * A138144 A138145 A138146

KEYWORD

easy,nonn,tabf

AUTHOR

Omar E. Pol (info(AT)polprimos.com), Mar 09 2008

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Apr 07 2008, Nov 15 2008

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Last modified February 15 21:56 EST 2012. Contains 205860 sequences.