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 A210827 Number of (n+1)X(n+1) 0..3 symmetric matrices with every 2X2 subblock having two distinct values, and new values 0..3 introduced in lower triangle row major order 0
 3, 29, 548, 18908, 1182512, 131061397, 25883001692, 9078760225423, 5673881364653895, 6325974204854627570, 12606596349780734850457, 44979541448033730855929795 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..12. EXAMPLE Some solutions for n=3 ..0..1..1..1....0..1..1..0....0..1..1..1....0..1..2..1....0..1..1..2 ..1..1..0..0....1..0..0..1....1..1..0..1....1..1..2..2....1..0..1..1 ..1..0..0..1....1..0..1..0....1..0..0..0....2..2..2..0....1..1..0..0 ..1..0..1..1....0..1..0..1....1..1..0..2....1..2..0..0....2..1..0..1 CROSSREFS Sequence in context: A113871 A186451 A248828 * A092251 A304553 A326337 Adjacent sequences: A210824 A210825 A210826 * A210828 A210829 A210830 KEYWORD nonn AUTHOR R. H. Hardin Mar 27 2012 STATUS approved

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Last modified December 2 13:50 EST 2023. Contains 367524 sequences. (Running on oeis4.)