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First differences of A140642.
1

%I #6 Dec 16 2014 05:36:32

%S 1,1,1,1,1,2,2,1,1,4,4,1,1,2,8,8,2,1,1,4,16,16,4,1,1,2,8,32,32,8,2,1,

%T 1,4,16,64,64,16,4,1

%N First differences of A140642.

%C (*) Main diagonal = A011782 but vertical = 1, A011782 unknown.

%F Also a triangle on line (*): 1; 1, 1; 1, 1, 2; 2, 1, 1, 4; 4, 1, 1, 2, 8; 8, 2, 1, 1, 4, 16; 16, 4, 1, 1, 2, 8, 32; 32, 8, 2, 1, 1, 4, 16, 64; Row sums:1, 2, 4, 8, 16 =A000079(n). Note even palindromes finishing a row and beginning next one.

%t maxTerm = 384; FixedPoint[(nMax++; Print["nMax = ", nMax]; jj = Table[(2^n - (-1)^n)/3, {n, 0, nMax}]; Table[Differences[jj, n], {n, 0, nMax}] // Flatten // Abs // Union // Select[#, 0 < # <= maxTerm &] &) &, nMax = 5 ] // Differences (* _Jean-François Alcover_, Dec 16 2014 *)

%K nonn,uned

%O 0,6

%A _Paul Curtz_, Jul 08 2008