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A108275 Number of positive integers <= 10^n that are divisible by no prime exceeding 17. 3

%I #9 Nov 14 2019 12:19:22

%S 1,10,67,287,945,2579,6179,13389,26809,50351,89679,152751,250420,

%T 397227,612185,919814,1351182,1945205,2750000,3824456,5239923,7082118,

%U 9453184,12473898,16286197,21055745,26974877,34265658,43183191,54019174

%N Number of positive integers <= 10^n that are divisible by no prime exceeding 17.

%t n = 10; t = Select[ Flatten[ Table[17^g* Select[ Flatten[ Table[13^f* Select[ Flatten[ Table[11^e* Select[ Flatten[ Table[7^d* Select[ Flatten[ Table[5^c* Select[ Flatten[ Table[2^a*3^b, {a, 0, n*Log[2, 10]}, {b, 0, n*Log[3, 10]}]], # <= 10^n &], {c, 0, n*Log[5, 10]}]], # <= 10^n &], {d, 0, n*Log[7, 10]}]], # <= 10^n &], {e, 0, n*Log[11, 10]}]], # <= 10^n &], {f, 0, n*Log[13, 10]}]], # <= 10^n &], {g, 0, n*Log[17, 10]}]], # <= 10^n &]; Table[ Length[ Select[t, # <= 10^n &]], {n, 0, 10}]

%Y Row 7 of A253635.

%Y Cf. A011557, A080681.

%K nonn

%O 0,2

%A _Robert G. Wilson v_, May 31 2005

%E a(11)-a(18) from _Donovan Johnson_, Sep 16 2009

%E a(19)-a(29) from _Max Alekseyev_, Apr 27 2010

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Last modified April 23 16:40 EDT 2024. Contains 371916 sequences. (Running on oeis4.)