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 A154726 Triangle read by rows in which row n lists: n, in the center of the row and the pairs of prime numbers that are equidistant to n, as shown below in the example. 12
 1, 2, 3, 3, 4, 5, 3, 5, 7, 5, 6, 7, 3, 7, 11, 3, 5, 8, 11, 13, 5, 7, 9, 11, 13, 3, 7, 10, 13, 17, 3, 5, 11, 17, 19, 5, 7, 11, 12, 13, 17, 19, 3, 7, 13, 19, 23, 5, 11, 14, 17, 23, 7, 11, 13, 15, 17, 19, 23, 3, 13, 16, 19, 29, 3, 5, 11, 17, 23, 29 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..10000 EXAMPLE Triangle begins:                        1                        2                        3                     3  4  5                  3  .  5  .  7               .  .  5  6  7  .  .            3  .  .  .  7  .  .  . 11         3  .  5  .  .  8  .  . 11  . 13      .  .  5  .  7  .  9  . 11  . 13  .  .   3  .  .  .  7  .  . 10  .  . 13  .  .  . 17 MAPLE for n from 1 to 10 do for k from 1 to 2*n-1 do if(k=n or (isprime(k) and isprime(2*n-k)))then print(k):fi:od:od: # Nathaniel Johnston, Apr 18 2011 CROSSREFS Cf. A000040, A154720, A154721, A154722, A154723, A154724, A154725, A154727. Sequence in context: A131282 A305296 A114544 * A325784 A244929 A302920 Adjacent sequences:  A154723 A154724 A154725 * A154727 A154728 A154729 KEYWORD easy,nonn,tabf AUTHOR Omar E. Pol, Jan 14 2009 EXTENSIONS a(31)-a(70) from Nathaniel Johnston, Apr 18 2011 STATUS approved

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Last modified August 23 11:24 EDT 2019. Contains 326222 sequences. (Running on oeis4.)