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A066809
a(n) = sum of modular offsets: mod[n+c,b]-(mod[n,b]+c) for c<=b<=n.
0
1, 3, 8, 13, 27, 34, 61, 76, 111, 136, 201, 213, 303, 354, 439, 490, 642, 682, 871, 935, 1107, 1234, 1509, 1535, 1834, 2011, 2298, 2438, 2872, 2937, 3432, 3619, 4049, 4350, 4905, 4956, 5658, 6033, 6634, 6844, 7704, 7871, 8816, 9180, 9874, 10421, 11548
OFFSET
1,2
EXAMPLE
1 = {1}, 3 = {1}+{0+2}, 8 = {1}+{2+2}+{0+0+3}, 13= {1}+{0+2}+{0+3+3}+{0+0+0+4}, 27= {1}+{2+2}+{3+3+3}+{0+0+4+4}+{0+0+0+0+5}, 34 = {1}+{0+2}+{0+0+3}+{0+4+4+4}+{0+0+0+5+5}+{0+0+0+0+0+6}.
MATHEMATICA
Table[ Sum[ -Mod[ n+c, b ]+Mod[ n, b ]+c, {b, n}, {c, b} ], {n, 64} ]
CROSSREFS
Sequence in context: A146939 A181540 A059028 * A009848 A337504 A355240
KEYWORD
nonn
AUTHOR
Wouter Meeussen, Jan 19 2002
STATUS
approved