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A230034 Numbers which can't be represented as a sum of 3 relatively prime positive integers such that each pair of them is not coprime. 2
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 50, 51, 52, 54, 56, 57, 58, 60, 62, 63, 64, 66, 68, 70, 72, 74, 75, 76, 78 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Complement of A230035.

a(n) is finite and contains exactly 156 terms.

Generally for every positive integer k there is only finite quantity of numbers which can't be represented as a sum of k + 1 relatively prime positive integers such that any k of them are not coprime.

For instance, for k = 3, 570570 is the largest number which cannot be represented.

LINKS

Table of n, a(n) for n=1..62.

Vladimir Letsko, Table of n, a(n) for n=1..156 (full sequence)

EXAMPLE

Every positive integer less than 31 is in the sequence because 31 obviously is the least number which can be represented as 2*3 + 2*5 + 3*5, j.e. as a sum of 3 relatively prime positive integers such that every pair of them is not coprime.

CROSSREFS

A230035

Sequence in context: A123068 A247064 A160547 * A269331 A246103 A281873

Adjacent sequences:  A230031 A230032 A230033 * A230035 A230036 A230037

KEYWORD

nonn,fini

AUTHOR

Vladimir Letsko, Dec 20 2013

STATUS

approved

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Last modified March 26 14:18 EDT 2019. Contains 321497 sequences. (Running on oeis4.)