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A233131
Sum of remainders of n modulo all smaller composite numbers.
2
0, 0, 0, 0, 0, 1, 2, 4, 2, 5, 9, 14, 9, 15, 21, 28, 24, 33, 27, 37, 33, 44, 56, 69, 52, 66, 81, 88, 87, 105, 92, 111, 102, 122, 143, 165, 139, 163, 187, 212, 196, 223, 209, 237, 239, 244, 274, 305, 266, 298, 296, 330, 335, 371, 347, 384, 368, 407, 447, 488, 432, 474, 516, 529, 513, 558, 543, 590, 599, 647, 637, 687, 620
OFFSET
0,7
FORMULA
a(n) = A004125(n) - A024934(n).
MATHEMATICA
Table[Total[Mod[n, Select[Range[n-1], CompositeQ]]], {n, 0, 80}] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 01 2018 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Max Alekseyev, Dec 07 2013
STATUS
approved