A209248 a(n) = 2^(2^n - 2*n - 1).

2, 128, 2097152, 2251799813685248, 10384593717069655257060992658440192, 883423532389192164791648750371459257913741948437809479060803100646309888

Offset: 3

Author

Jonathan Vos Post, Jan 13 2013

Keywords

• nonn
• easy

Comments

a(n) = 2^A070313(n). Krotov on p. 2: "in general, two extended Hamming codes can intersect in 2^(2^m - 2m - 1) elements."

Examples

			a(5) = 2^(2^5 - 2*5 - 1) = 2^21 = 2097152.
		

Links

• Denis Krotov, A partition of the hypercube into cosets of maximally nonparallel Hamming codes, arXiv:1210.0010v1 [cs.IT], 2012-2016.
• Index to divisibility sequences

Crossrefs

Cf. A070313.

Programs

Mathematica

Table[2^(2^n - 2n - 1), {n, 3, 15}] (* Alonso del Arte, Jan 13 2013 *)

Maxima

makelist(floor(2^(2^n-2*n-1)),n,3,8); /* Martin Ettl, Jan 25 2013 */

PARI

1<<(2^n-2*n-1) \\ Charles R Greathouse IV, Jan 24 2013