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A232009 a(n) = the smallest squarefree number (from A005117) of the form p*q with prime factors in a p^2 + n progression, or 0 if no such number exists. 3
10, 33, 14, 39, 0, 155, 22, 51, 26, 57, 0, 185, 34, 69, 38, 205, 0, 215, 46, 87, 0, 93, 0, 511, 58, 0, 62, 111, 0, 553, 0, 123, 74, 129, 0, 305, 82, 141, 86, 623, 0, 335, 94, 159, 0, 355, 0, 365, 106, 177, 0, 183, 0, 395, 118, 0, 122, 201, 0, 763, 0, 213, 134 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = the smallest squarefree number m of the form p*q with prime factors p and q = p^2 + n, or 0 if no such number exists; m = p^3 + p*n.

a(n) = 0 for numbers n from A232010.

LINKS

Table of n, a(n) for n=1..63.

FORMULA

a(4) = 39 because 39 = 3 * 13 = 3 * (3^2 + 4).

CROSSREFS

Cf. A005117, A232010, A067775, A232012, A023200.

Sequence in context: A120969 A265374 A231032 * A137723 A256352 A255533

Adjacent sequences:  A232006 A232007 A232008 * A232010 A232011 A232012

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Nov 20 2013

STATUS

approved

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Last modified August 26 00:35 EDT 2019. Contains 326324 sequences. (Running on oeis4.)