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 A271047 A prime number sieve defined by the recurrence: T(n, k) = If n = k then 1 else if k divides n then -Sum_{i=k+1..n} T(n, i) else T(n,k) = 0. 0
 1, -1, 1, -1, 0, 1, 0, -1, 0, 1, -1, 0, 0, 0, 1, 0, 0, -1, 0, 0, 1, -1, 0, 0, 0, 0, 0, 1, 0, 0, 0, -1, 0, 0, 0, 1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1 COMMENTS Same negative sum as in the recurrence for the MÃ¶bius function except that it is applied at all the divisors and not only in the first column. The table therefore acts as a prime number sieve giving the characteristic sequence of prime numbers in the first column. Row sums are 1,0,0,0,0,0,0,0,0,... LINKS FORMULA T(n, k) = If n = k then 1 else if k divides n then -Sum_{i=k+1..n} T(n, i) else T(n,k) = 0. EXAMPLE { {1}, {-1, 1}, {-1, 0, 1}, {0, -1, 0, 1}, {-1, 0, 0, 0, 1}, {0, 0, -1, 0, 0, 1}, {-1, 0, 0, 0, 0, 0, 1}, {0, 0, 0, -1, 0, 0, 0, 1}, {0, 0, -1, 0, 0, 0, 0, 0, 1}, {0, 0, 0, 0, -1, 0, 0, 0, 0, 1}, {-1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}, {0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 1} } MATHEMATICA (* recurrence *) Clear[t, n, k, nn]; nn = 12; t[n_, k_] := t[n, k] = If[n == k, 1, If[Mod[n, k] == 0, -Sum[t[n, i], {i, k + 1, n}], 0]]; Flatten[Table[Table[t[n, k], {k, 1, n}], {n, 1, nn}]] CROSSREFS Sequence in context: A115952 A115524 A117198 * A054525 A174852 A065333 Adjacent sequences:  A271044 A271045 A271046 * A271048 A271049 A271050 KEYWORD sign AUTHOR Mats Granvik, Mar 29 2016 STATUS approved

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Last modified September 20 01:52 EDT 2019. Contains 327207 sequences. (Running on oeis4.)