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A276936 Numbers n with at least one distinct prime factor prime(k) such that prime(k)^k divides, but prime(k)^(k+1) does not divide n. 4
2, 6, 9, 10, 14, 18, 22, 26, 30, 34, 36, 38, 42, 45, 46, 50, 54, 58, 62, 63, 66, 70, 72, 74, 78, 82, 86, 90, 94, 98, 99, 102, 106, 110, 114, 117, 118, 122, 125, 126, 130, 134, 138, 142, 144, 146, 150, 153, 154, 158, 162, 166, 170, 171, 174, 178, 180, 182, 186, 190, 194, 198, 202, 206, 207, 210, 214, 218, 222, 225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n with at least one prime factor such that the exponent of its highest power in n is equal to the index of that prime.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..5500

EXAMPLE

2 is a member as 2 = prime(1) and as 2^1 divides but 2^2 does not divide 2.

3 is NOT a member as 3 = prime(2) but 3^2 does not divide 3.

4 is NOT a member as 2^2 divides 4.

6 is a member as 2 = prime(1) and 2^1 is a divisor of 6, but 2^2 is not.

9 is a member as 3 = prime(2) and 3^2 divides 9.

PROG

(Scheme, with Antti Karttunen's IntSeq-library)

(define A276936 (NONZERO-POS 1 1 A276935))

CROSSREFS

Cf. A276935.

Intersection with A276078 gives A276937.

Cf. A016825, A051063 (subsequences).

Sequence in context: A285532 A016726 A047396 * A276937 A243373 A085304

Adjacent sequences:  A276933 A276934 A276935 * A276937 A276938 A276939

KEYWORD

nonn

AUTHOR

Antti Karttunen, Sep 24 2016

STATUS

approved

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Last modified January 20 16:20 EST 2019. Contains 319335 sequences. (Running on oeis4.)