A077621 -id:A077621 - cp's OEIS frontend

A077619 Number of occurrences of n-th squarefree number in A076734.

1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1

Offset: 1

Reinhard Zumkeller, Nov 12 2002

nonn

Amiram Eldar, Table of n, a(n) for n = 1..10000

Cf. A005117, A076734, A077618, A077620, A077621, A077622.

a(n) = A077618(A005117(n)).

A077618(a(n)) > 0.

A077620 Numbers occurring only once in A076734.

Original entry on oeis.org

1, 2, 3, 5, 7, 11, 13, 14, 15, 17, 19, 21, 22, 23, 29, 31, 33, 34, 35, 37, 38, 39, 41, 42, 43, 46, 47, 53, 55, 57, 58, 59, 61, 62, 65, 67, 69, 71, 73, 74, 77, 79, 82, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 101, 103, 105, 106, 107, 109, 110, 111, 113, 114, 115, 118, 119

Offset: 1

Reinhard Zumkeller, Nov 12 2002

nonn

Primes are a subsequence: A077618(A000040(n)) = 1.

Amiram Eldar, Table of n, a(n) for n = 1..10000

Cf. A076734, A077618, A077619, A077621.

A077618(a(n)) = 1.

A077622 Number of numbers <= prime(n)# having n prime factors (with multiplicity), where prime(n)# = A002110(n) is the n-th primorial.

Original entry on oeis.org

1, 2, 7, 27, 190, 1621, 17271, 200536, 2757881, 47108763, 843069901, 17797435824

Offset: 1

Reinhard Zumkeller, Nov 12 2002

nonn

a(n) = A077618(A002110(n)), see A077621.

			a(3)=7, as there are 7 numbers <= prime(3)# = 2*3*5 = 30 having 3 prime factors: 8=2*2*2, 12=2*2*3, 18=2*3*3, 20=2*2*5, 27=3*3*3, 28=2*2*7 and 30=2*3*5.

Cf. A001222.

17271 from Sascha Kurz, Jan 04 2003
a(8)-a(11) from Donovan Johnson, Nov 15 2009
a(12) from Donovan Johnson, Jul 16 2011

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A077619 Number of occurrences of n-th squarefree number in A076734.

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A077620 Numbers occurring only once in A076734.

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A077622 Number of numbers <= prime(n)# having n prime factors (with multiplicity), where prime(n)# = A002110(n) is the n-th primorial.

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