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 A034349 Number of binary [ n,8 ] codes without 0 columns. 7
 0, 0, 0, 0, 0, 0, 0, 1, 8, 47, 277, 1775, 12616, 102445, 957357, 10174566, 119235347, 1482297912, 18884450721, 240477821389, 3012879828566, 36800049400028, 436068618826236, 5001537857507095, 55482177298724426, 595303034603214108, 6181562837200509792, 62170512250565592346 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,9 COMMENTS To find the g.f., modify the Sage program below (cf. function f). It is very complicated to write it here. - Petros Hadjicostas, Oct 07 2019 LINKS Discrete algorithms at the University of Bayreuth, Symmetrica. Harald Fripertinger, Isometry Classes of Codes. Harald Fripertinger, Snk2: Number of the isometry classes of all binary (n,k)-codes without zero-columns. [See column k=8.] H. Fripertinger and A. Kerber, Isometry classes of indecomposable linear codes. In: G. Cohen, M. Giusti, T. Mora (eds), Applied Algebra, Algebraic Algorithms and Error-Correcting Codes, 11th International Symposium, AAECC 1995, Lect. Notes Comp. Sci. 948 (1995), pp. 194-204. [Here a(n) = S_{n,8,2}.] Petr Lisonek, Combinatorial families enumerated by quasi-polynomials, J. Combin. Theory Ser. A 114(4) (2007), 619-630. [See Section 5.] David Slepian, Some further theory of group codes, Bell System Tech. J. 39(5) (1960), 1219-1252. David Slepian, Some further theory of group codes, Bell System Tech. J. 39(5) (1960), 1219-1252. Wikipedia, Cycle index. Wikipedia, Projective linear group. PROG (Sage) # Fripertinger's method to find the g.f. of column k >= 2 of A034253 (for small k): def A034253col(k, length):     G1 = PSL(k, GF(2))     G2 = PSL(k-1, GF(2))     D1 = G1.cycle_index()     D2 = G2.cycle_index()     f1 = sum(i*prod(1/(1-x^j) for j in i) for i in D1)     f2 = sum(i*prod(1/(1-x^j) for j in i) for i in D2)     f = f1 - f2     return f.taylor(x, 0, length).list() # For instance the Taylor expansion for column k = 8 (current sequence) gives print(A034253col(8, 30)) # Petros Hadjicostas, Oct 07 2019 CROSSREFS Cf. A034254, A034344, A034345, A034346, A034347, A034348, A253186. Column k=8 of A034253 and first differences of A034362. Sequence in context: A014524 A098891 A054488 * A296797 A024108 A247726 Adjacent sequences:  A034346 A034347 A034348 * A034350 A034351 A034352 KEYWORD nonn AUTHOR EXTENSIONS More terms from Petros Hadjicostas, Oct 07 2019 STATUS approved

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Last modified May 7 20:36 EDT 2021. Contains 343652 sequences. (Running on oeis4.)