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A140589 Triangle A(k,n) = (-2)^k+2^n read by rows. 1
2, -1, 0, 5, 6, 8, -7, -6, -4, 0, 17, 18, 20, 24, 32, -31, -30, -28, -24, -16, 0, 65, 66, 68, 72, 80, 96, 128, -127, -126, -124, -120, -112, -96, -64, 0, 257, 258, 260, 264, 272, 288, 320, 384, 512, -511, -510, -508, -504, -496, -480, -448, -384, -256, 0, 1025, 1026, 1028, 1032 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
The flattened sequence a(A000217(k)+j)=A(k,j) obeys a(n+1)-2a(n)= -5, 2, 5, -4, -4, -23, 8, 8, 8, 17, -16, -16, -16, -16, -95, ..., which is a dispersion of 2, -4, -4, 8, 8, 8, ... (a signed version of A140513) with -5, 5, -23, 17, -95, 65,... The latter sequence is A(k,0)-2*A(k-1,k-1), an alternation of the negative of A140529 with each second element of A000051.
LINKS
Dana G. Korssjoen, Biyao Li, Stefan Steinerberger, Raghavendra Tripathi, and Ruimin Zhang, Finding structure in sequences of real numbers via graph theory: a problem list, arXiv:2012.04625, Dec 08, 2020
FORMULA
A(k,n) = A000079(n)+A122803(k).
EXAMPLE
Rows starting at k=0: (2), (-1,0); (5, 6, 8); (-7,-6,-4,0); (17,18,20,24,32);...
CROSSREFS
Sequence in context: A054651 A292323 A059720 * A331955 A185209 A316659
KEYWORD
sign,tabl
AUTHOR
Paul Curtz, Jul 06 2008
EXTENSIONS
Edited by R. J. Mathar, Jul 08 2008
STATUS
approved

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Last modified April 16 12:05 EDT 2024. Contains 371711 sequences. (Running on oeis4.)