login
A174743
Partial sums of A076766.
0
1, 3, 7, 15, 31, 63, 131, 279, 621, 1469, 3766, 10694, 34728, 133582, 636719, 3955451, 33664265, 407703531, 7147333784, 180948983492, 6537204164708, 332740721681412, 23627093701822296, 2324803141466748032, 315610211340647518667, 58953876234603150481383
OFFSET
0,2
COMMENTS
Number of inequivalent binary linear codes of length <= n. Also the total number of nonisomorphic binary matroids on an k-set for all k <= n. The subsequence of primes is: 3, 7, 31, 131.
EXAMPLE
a(14) = 1 + 2 + 4 + 8 + 16 + 32 + 68 + 148 + 342 + 848 + 2297 + 6928 + 24034 + 98854 + 503137 = 636719 is prime.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Nov 30 2010
STATUS
approved