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A171378 Zeros in a Pascal modulo two matrix:a(n)=(n+1)^2-A006046(n) 1
0, 1, 4, 7, 14, 21, 30, 37, 52, 67, 84, 99, 120, 139, 160, 175, 206, 237, 270, 301, 338, 373, 410, 441, 486, 529, 574, 613, 662, 705, 750, 781, 844, 907, 972, 1035, 1104, 1171, 1240, 1303, 1380, 1455, 1532, 1603, 1684, 1759, 1836, 1899, 1992, 2083, 2176, 2263 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The sequence is the relationship of holes to fractal by area of Sierpinski gasket modulo two matrices.

The area ratio: a(n)/(n+1)^2 varies fractally while approaching a limit near 0.876581.

LINKS

Robert Price, Table of n, a(n) for n = 0..999

MATHEMATICA

TableForm[Table[Table[Table[Mod[ Binomial[m, k], 2], {k, 0, n}], {m, 0, n}], {n, 0, 10}]]

(*A006046*)

Table[Sum[Sum[Mod[Binomial[m, k], 2], {k, 0, m}], {m, 0, n}], {n, 0, 30}]

Table[(n + 1)^2 - Sum[Sum[Mod[Binomial[ m, k], 2], {k, 0, m}], {m, 0, n}], {n, 0, 100}]

CROSSREFS

Cf. A006046, A001316

Sequence in context: A115759 A157615 A188319 * A147478 A147372 A201272

Adjacent sequences:  A171375 A171376 A171377 * A171379 A171380 A171381

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, Dec 07 2009

STATUS

approved

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Last modified November 22 05:36 EST 2017. Contains 295076 sequences.