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A145583 a(n)=number of numbers removed in each step of Eratosthenes' sieve for 10^2 11
49, 16, 6, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of steps in Eratosthenes' sieve for 10^n is A122121(n).

Number of primes less than 10^2 is equal = 10^2 - (sum all of numbers in this sequence) - 1 = A006880(2).

LINKS

Table of n, a(n) for n=1..4.

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 = 2; kk = PrimePi[Sqrt[10^nn]]; t3 = f3[10^nn, kk] (*Bob Hanlon (hanlonr(AT)cox.net) *)

CROSSREFS

A006880, A122121, A145532-A145540, A145583-A145592

Sequence in context: A012120 A278107 A218167 * A304139 A305045 A065787

Adjacent sequences:  A145580 A145581 A145582 * A145584 A145585 A145586

KEYWORD

fini,nonn

AUTHOR

Artur Jasinski with assistance from Bob Hanlon (hanlonr(AT)cox.net), Oct 14 2008

STATUS

approved

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Last modified January 27 09:01 EST 2020. Contains 331293 sequences. (Running on oeis4.)