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A240113 Integers for which the smallest m in A040081 such that n*2^m - 1 is prime (A038699) increases. 1
1, 13, 23, 43, 59, 88, 127, 148, 659 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Where records occur in A040081. A103963 gives the record values.

The next candidate is 2293.

LINKS

Table of n, a(n) for n=1..9.

Wilfrid Keller, The Riesel Problem: Definition and Status

PROG

(PARI) a=0; for(n=1, 148, m=0; while(!ispseudoprime(n*2^m-1), m++); if(m>a, a=m; print1(n, ", ")));

CROSSREFS

Cf. A038699, A040081, A103963.

Sequence in context: A236418 A112394 A067227 * A256177 A320752 A213665

Adjacent sequences:  A240110 A240111 A240112 * A240114 A240115 A240116

KEYWORD

nonn,more

AUTHOR

Arkadiusz Wesolowski, Apr 01 2014

STATUS

approved

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Last modified September 27 07:02 EDT 2021. Contains 347673 sequences. (Running on oeis4.)