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A178684
Partial sums of cardinalities of coalition sets A095941.
0
0, 0, 1, 5, 18, 53, 138, 332, 757, 1661, 3546, 7424, 15328, 31336, 63618, 128531, 258811, 519956, 1042992, 2090009, 4185231, 8377158, 16762853, 33536516, 67086633, 134190278, 268401718, 536829625, 1073691505, 2147422558
OFFSET
1,4
COMMENTS
Partial sums of number of subsets of {1,2,...,n} such that every number in the set is no larger than the sum of the other numbers in the set. See formula in A095944. The subsequence of primes begins: 5, 53, 757, 2090009, 16762853.
EXAMPLE
a(9) = 0 + 0 + 1 + 4 + 13 + 35 + 85 + 194 + 425 = 757 is prime.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jonathan Vos Post, Dec 25 2010
STATUS
approved