A275079 The number of 2-compositions of n of Carlitz type.

1, 2, 5, 18, 53, 162, 505, 1548, 4756, 14650, 45065, 138622, 426528, 1312242, 4037155, 12420806, 38213753, 117567880, 361708733, 1112830322, 3423724282, 10533403974, 32406988208, 99703082744, 306745721586, 943731474930

Offset

0,2

Links

Table of n, a(n) for n=0..25.

E. Munarini, M. Poneti, S. Rinaldi, Matrix compositions, JIS 12 (2009) 09.4.8, Table 3.

Maple

m := 2 ;
kmax := 30 ;
add((-1)^k*(1-(1-x^k)^m)/(1-x^k)^m, k=1..kmax) ;
1/(1+%) ;
taylor(%, x=0, kmax-1) ;
gfun[seriestolist](%) ;

Crossrefs

Cf. A003242 (1-compositions).

Sequence in context: A295905 A056296 A293964 * A148417 A148418 A148419

Adjacent sequences: A275076 A275077 A275078 * A275080 A275081 A275082

Keyword

nonn

Author

R. J. Mathar, Jul 15 2016

Status

approved