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A226977 Places n where A225867(n) <= 2. 2
7, 8, 11, 17, 23, 29, 41, 47, 59, 71, 239, 359, 419, 839 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except for a(2)=8, all terms are prime.

Is this sequence finite?

There are no other terms up to 86000. - Peter J. C. Moses, Jun 28 2013

There are no more terms up to 10^9. - Charles R Greathouse IV, Nov 25 2014

LINKS

Table of n, a(n) for n=1..14.

PROG

(PARI) is(n)=for(k=2, n\2-1, if(sumdiv(n+k, d, (n+d)%k==0 && d>1)>2, return(0))); n>6 \\ Charles R Greathouse IV, Nov 25 2014

CROSSREFS

Cf. A225867, A049002.

Sequence in context: A145826 A102963 A117619 * A098731 A294483 A105740

Adjacent sequences:  A226974 A226975 A226976 * A226978 A226979 A226980

KEYWORD

nonn,more

AUTHOR

Vladimir Shevelev, Jun 27 2013

STATUS

approved

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Last modified April 21 22:12 EDT 2019. Contains 322328 sequences. (Running on oeis4.)