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A084409
Main diagonal of triangle A084408.
3
1, 3, 11, 9, 29, 18, 59, 28, 40, 54, 107, 69, 179, 87, 106, 125, 271, 147, 389, 172, 200, 224, 541, 254, 286, 316, 346, 381, 727, 416, 941, 455, 495, 534, 575, 620, 1201, 665, 710, 756, 1493, 804, 1823, 856, 909, 962, 2203, 1018, 1077, 1136, 1194, 1254, 2621
OFFSET
1,2
COMMENTS
a(n) is prime iff n is prime.
FORMULA
For n prime, a(n) = p(A034387(n)). For n composite, a(n) = A002808([n*(n+1)/2]-A034387(n)-1).
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, Jun 01 2003
EXTENSIONS
Edited and extended by David Wasserman, Dec 27 2004
STATUS
approved