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A213424
Number of partitions of n in which all parts are >= 2 and the largest part occurs at least five times.
0
1, 0, 1, 0, 1, 1, 1, 1, 2, 1, 3, 2, 3, 3, 5, 4, 6, 6, 8, 8, 12, 10, 15, 15, 19, 21, 26, 26, 34, 36, 45, 47, 59, 61, 76, 83, 97, 107, 128, 137, 165, 179, 210, 231, 271, 296, 345, 380, 438, 485, 561, 614, 708, 783, 893, 991, 1129, 1246, 1420, 1572, 1781
OFFSET
10,9
FORMULA
a(n) = A186445(n) - 2*A186445(n-1) + A186445(n-2).
G.f.: (1-x)*Product_{k>4} 1/(1-x^k)
EXAMPLE
For n = 20 we have three partitions: {[4+4+4+4+4], [3+3+3+3+3+3+2], [2+2+2+2+2+2+2+2+2+2]}, so a(20) = 3.
CROSSREFS
KEYWORD
nonn
AUTHOR
Mircea Merca, Jun 11 2012
STATUS
approved