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Search: id:A052349
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A052349 a(n) = smallest nonprime such that every subset of a(1), ..., a(n) adds to a nonprime. +0
10
1, 8, 24, 25, 86, 1260, 1890, 14136, 197400, 10467660, 1231572090 (list; graph; listen)
OFFSET

1,2

COMMENT

This set was defined by T. W. A. Baumann for The Prime Puzzles and Problems pages. He and C. Rivera obtained the first 10 members. Chris Nash proved that this sequence is infinite.

LINKS

Carlos Rivera, Puzzle 84

EXAMPLE

a(4) = 25 as 25+1, 25+8, 25+24, 25+1+8, 25+1+24, 25+8+24 and finally 25+1+8+24 all are composite numbers.

CROSSREFS

Cf. A068638.

Cf. A128687 (restricted to odd numbers), A128688 (restricted to even numbers).

Sequence in context: A005878 A128637 A109272 this_sequence A029607 A060476 A048109

Adjacent sequences: A052346 A052347 A052348 this_sequence A052350 A052351 A052352

KEYWORD

hard,nonn,nice

AUTHOR

Carlos B. Rivera F. (crivera(AT)primepuzzles.net), Mar 07 2000

EXTENSIONS

One more term from T. D. Noe (noe(AT)sspectra.com), Mar 20 2007

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Last modified November 23 10:40 EST 2009. Contains 167421 sequences.


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