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A077225 Starting with a(0)=1, smallest squarefree number k such that, for all a(m), m<n, k+a(m) is not squarefree. 3
1, 3, 15, 17, 233, 291, 577, 723, 1455, 3615, 8117, 8835, 9505, 30833, 128773, 130827, 239595, 273435, 426891, 654135, 676297, 926117, 145553, 1662533, 2389517, 2762427, 2820927, 7994449, 8098527, 14319073, 16766835, 20506733, 27606617 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..32.

EXAMPLE

17 belongs to this sequence as 17+1, 17+3, 17+15 all are divisible by some square.

PROG

(PARI) v=vector(60):v[1]=1:print1("1, "):for(n=2, 60, for(k=1, 10^15, if(issquarefree(k), s=0:for(l=1, n-1, if(issquarefree(k+v[l]), break):s=s+1)): if(s==n-1, print1(k", "):v[n]=k:break)))

CROSSREFS

Cf. A077224.

Sequence in context: A032921 A163785 A080793 * A236526 A039559 A045753

Adjacent sequences:  A077222 A077223 A077224 * A077226 A077227 A077228

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Nov 03 2002

EXTENSIONS

Edited by Ralf Stephan, Mar 25 2003

More terms from Sam Alexander, Dec 12 2003

STATUS

approved

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Last modified September 26 16:08 EDT 2021. Contains 347669 sequences. (Running on oeis4.)