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A145536
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a(n)=number of numbers removed in each step of Eratosthenes' sieve for 9!
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2
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181439, 60479, 24191, 13823, 7540, 5800, 4092, 3446, 2701, 2046, 1842, 1487, 1296, 1200, 1070, 927, 817, 782, 703, 665, 645, 600, 574, 538, 498, 477, 465, 451, 441, 425, 385, 372, 351, 346, 326, 322, 308, 294, 288, 277, 267, 263, 248, 246, 238, 236, 221, 211
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Number of steps in Eratosthenes' sieve for n! is A133228(n).
Number of primes less than 9! is equal = 9!-(sum all numbers in this sequence)-1 = A003604(9).
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LINKS
| Nathaniel Johnston, Table of n, a(n) for n = 1..110 (full sequence)
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MAPLE
| A145536:=Array([seq(0, j=1..110)]): lim:=9!: p:=Array([seq(ithprime(j), j=1..110)]): for n from 4 to lim do if(isprime(n))then n:=n+1: fi: for k from 1 to 110 do if(n mod p[k] = 0)then A145536[k]:=A145536[k]+1: break: fi: od: od: seq(A145536[j], j=1..110); # Nathaniel Johnston, Jun 23 2011
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MATHEMATICA
| f3[k_Integer?Positive, i_Integer?Positive] := Module[{f, m, r, p}, p = Transpose[{r = Range[2, i], Prime[r]}]; f[x_] := Catch[Fold[If[Mod[x, #2[[2]]] == 0, Throw[m[ #2[[1]]] = m[ #2[[1]]] + 1], #1] &, If[Mod[x, 2] == 0, Throw[m[1] = m[1] + 1]], p]]; Table[m[n] = -1, {n, i}]; f /@ Range[k]; Table[m[n], {n, i}]]; nn = 9; kk = PrimePi[Sqrt[nn! ]]; t3 = f3[nn!, kk] (*Bob Hanlon*)
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CROSSREFS
| A003604, A133228, A145532-A145540
Sequence in context: A060232 A190380 A133541 * A030466 A086478 A024754
Adjacent sequences: A145533 A145534 A145535 * A145537 A145538 A145539
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KEYWORD
| fini,nonn
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AUTHOR
| Artur Jasinski with assistence from Bob Hanlon (grafix(AT)csl.pl), Oct 14 2008
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