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A257352
G.f.: (1-2*x+51*x^2)/(1-x)^3.
7
1, 1, 51, 151, 301, 501, 751, 1051, 1401, 1801, 2251, 2751, 3301, 3901, 4551, 5251, 6001, 6801, 7651, 8551, 9501, 10501, 11551, 12651, 13801, 15001, 16251, 17551, 18901, 20301, 21751, 23251, 24801, 26401, 28051, 29751, 31501, 33301
OFFSET
0,3
COMMENTS
An example of a quadratic sequence for which the continued square root map (see A257574) produces the number 2. There are infinitely many sequences with this property - another example is A028387.
LINKS
Popular Computing (Calabasas, CA), The CSR Function, Vol. 4 (No. 34, Jan 1976), pages PC34-10 to PC34-11. Annotated and scanned copy.
Herman P. Robinson, The CSR Function, Popular Computing (Calabasas, CA), Vol. 4 (No. 35, Feb 1976), pages PC35-3 to PC35-4. Annotated and scanned copy.
PROG
(PARI) a(n)=25*n^2-25*n+1 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
Sequence in context: A348000 A044383 A044764 * A353599 A008883 A327624
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, May 03 2015
STATUS
approved