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A139597 A139278(n) followed by A139274(n+1). 6
0, 7, 15, 30, 46, 69, 93, 124, 156, 195, 235, 282, 330, 385, 441, 504, 568, 639, 711, 790, 870, 957, 1045, 1140, 1236, 1339, 1443, 1554, 1666, 1785, 1905, 2032, 2160, 2295, 2431, 2574, 2718, 2869, 3021, 3180, 3340, 3507, 3675, 3850 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Sequence found by reading the line from 0, in the direction 0, 7,... and the line from 15, in the direction 15, 46,..., in the square spiral whose vertices are the triangular numbers A000217.

LINKS

O. E. Pol, Determinacion geometrica de los numeros primos y perfectos.

FORMULA

Array read by rows: row n gives 8*n^2 + 7n, 8*(n+1)^2 - (n+1).

EXAMPLE

Array begins:

0, 7

15, 30

46, 69

93, 124

CROSSREFS

Cf. A000217, A046092, A139274, A139278, A077221, A139591, A139592, A139593, A139595, A139596, A139598.

Sequence in context: A195041 A006188 A198589 * A117747 A179882 A137196

Adjacent sequences:  A139594 A139595 A139596 * A139598 A139599 A139600

KEYWORD

easy,nonn

AUTHOR

Omar E. Pol (info(AT)polprimos.com), May 03 2008

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Last modified February 17 14:19 EST 2012. Contains 206038 sequences.