A173809 - OEIS

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A173809

a(2n+1) = 1+A131941(2n+1). a(2n) = A131941(2n).

2, 3, 9, 16, 30, 47, 73, 104, 146, 195, 257, 328, 414, 511, 625, 752, 898, 1059, 1241, 1440, 1662, 1903, 2169, 2456, 2770, 3107, 3473, 3864, 4286, 4735, 5217, 5728, 6274, 6851, 7465, 8112, 8798, 9519, 10281, 11080 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	COMMENTS	`An array T(n,k) of a(n) and its successive differences is T(1,k) = a(k), T(n,k) = T(n-1,k+1)-T(n-1,k) and starts:` `2, 3, 9, 16, 30, 47, 73, 104, 146, 195, 257, 328,...` `1, 6, 7, 14, 17, 26, 31, 42, 49, 62, 71, 86, 97, 114,... interleaved A056220 and A051890` `5, 1, 7, 3, 9, 5, 11, 7, 13, 9, 15, 11, 17, 13, 19, 15.... A158552` `-4, 6, -4, 6, -4, 6, -4, 6, -4, 6, -4, 6, -4, 6, -4,... A010711` `10, -10, 10, -10, 10, -10, 10, -10, 10, -10, 10,..`
	LINKS	`Table of n, a(n) for n=1..40.` `Index to sequences with linear recurrences with constant coefficients, signature (3,-2,-2,3,-1).`
	FORMULA	`G.f.: -x(-2+3x+x^3-4x^2) / ( (1+x)(x-1)^4 ). - R. J. Mathar, Jan 13 2011` `a(2n) = A172482(n-1).` `a(n)+a(n+1) = A116731(n+2). - R. J. Mathar, Jan 13 2011`
	CROSSREFS	`Sequence in context: A054416 A092638 A206777 * A023147 A220123 A220125` `Adjacent sequences: A173806 A173807 A173808 * A173810 A173811 A173812`
	KEYWORD	`nonn,easy`
	AUTHOR	`Paul Curtz, Feb 25 2010`
	STATUS	`approved`

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Last modified May 18 18:50 EDT 2013. Contains 225423 sequences.