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A056228
Image of Euler totient function (A000010) under "little Hankel" transform that sends [c_0, c_1, ...] to [d_0, d_1, ...] where d_n = c_n^2 - c_{n+1}*c_{n-1}.
0
-1, 2, -4, 12, -20, 28, -20, 20, -44, 84, -104, 120, -60, 16, -64, 208, -252, 276, -152, 64, -164, 404, -376, 304, -216, 180, -360, 688, -776, 772, -344, 144, -224, 384, -720, 1080, -540, 288, -704, 1408, -1536, 1524, -608, 136, -620, 1764, -1676, 1444, -944, 544
OFFSET
1,2
CROSSREFS
Sequence in context: A129021 A290440 A090922 * A166869 A168380 A335730
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Aug 06 2000
STATUS
approved