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A224563 Number of (n+3) X 6 0..1 matrices with each 4 X 4 subblock idempotent. 1
512, 428, 514, 629, 728, 929, 1232, 1627, 2095, 2739, 3658, 4945, 6670, 9010, 12237, 16720, 22894, 31375, 43047, 59167, 81423, 112123, 154455, 212868, 293495, 404781, 558355, 770299, 1062824, 1466590, 2023882, 2793071, 3854735, 5320116, 7342737 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A224568.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 3*a(n-1) - 2*a(n-2) - 2*a(n-3) + 4*a(n-4) - 3*a(n-5) + 2*a(n-7) - a(n-8) for n>10.

Empirical g.f.: x*(512 - 1108*x + 254*x^2 + 967*x^3 - 1323*x^4 + 855*x^5 + 387*x^6 - 753*x^7 + 167*x^8 + 40*x^9) / ((1 - x)^3*(1 + x)*(1 - x - x^4)). - Colin Barker, Sep 01 2018

EXAMPLE

Some solutions for n=3:

..1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..0..0

..1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0

..0..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..0..1

..0..0..0..0..0..0....0..0..0..0..0..0....1..0..0..0..1..0....0..0..0..0..0..1

..0..0..0..0..0..0....0..0..0..0..0..0....1..0..0..0..1..0....1..0..0..0..0..1

..0..1..1..1..1..1....0..0..0..1..1..1....0..0..0..0..1..0....0..0..0..0..0..1

CROSSREFS

Cf. A224568.

Sequence in context: A190025 A077743 A111447 * A217849 A326113 A045003

Adjacent sequences:  A224560 A224561 A224562 * A224564 A224565 A224566

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 10 2013

STATUS

approved

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Last modified January 19 08:18 EST 2022. Contains 350464 sequences. (Running on oeis4.)