A140643 First differences of A140642.

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, 64, 16, 4, 1

Offset: 0

Author

Paul Curtz, Jul 08 2008

Keywords

• nonn
• uned

Comments

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

Programs

Mathematica

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 *)

Formula

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.