A256474 Numbers n for which there are at least as many primes in the range [prime(n)*prime(n+1), prime(n+1)^2] as in the range [prime(n)^2, prime(n)*prime(n+1)].

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 40, 46, 47, 51, 52, 53, 54, 56, 57, 60, 62, 64, 66, 67, 68, 70, 71, 72, 75, 76, 78, 79, 80, 82, 83, 84, 85, 87, 89, 90, 91, 93, 94, 95, 97, 99, 100

Offset

1,2

Comments

Positions of nonnegative terms in A256470.

Links

Antti Karttunen, Table of n, a(n) for n = 1..3457

Mathematica

Select[Range@100, Count[Range[Prime[#] Prime[# + 1], Prime[# + 1]^2], _?PrimeQ] >= Count[Range[Prime[#]^2, Prime[#] Prime[# + 1]], _?PrimeQ] &] (* Michael De Vlieger, Mar 30 2015 *)

Prog

(Scheme, with Antti Karttunen's IntSeq-library)
(define A256474 (MATCHING-POS 1 1 (lambda (n) (<= 0 (A256470 n)))))

Crossrefs

Complement: A256475.

Union of A256471 and A256476.

Cf. A256484 (corresponding primes).

Cf. A256470.

Sequence in context: A371968 A335467 A374768 * A085824 A351290 A374249

Adjacent sequences: A256471 A256472 A256473 * A256475 A256476 A256477

Keyword

nonn

Author

Antti Karttunen, Mar 30 2015

Status

approved