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A205532 Primes at which occur records of A205531 and A205535. 4
2, 13, 61, 109, 1009, 2689, 8089, 33049, 53881, 87481, 483289, 515761, 1083289, 3818929, 9257329 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Related to the 4.X Selfridge Conjecture by P. Underwood, cf. link.

Records occur at [A205532(n), A205534(n)] = [2, 1], [13, 3], [61, 5], [109, 6], [1009, 9], [2689, 11], [8089, 15], [33049, 17], [53881, 21], [87481, 27], [483289, 29], [515761, 35], [1083289, 39], [3818929, 45], [9257329, 51],...

It appears that a(n)=A102295(n+1) for n>4; they are also terms of A002224 and A096637.

LINKS

Table of n, a(n) for n=1..15.

P. Underwood, 4.X Selfridge Conjecture (on "Prime Pages" profile), Jan 2012.

PROG

(PARI) m=-1; forprime(p=1, default(primelimit), if(m+0<m=max(m, A205535(p), m), print1(p", ")))

CROSSREFS

Sequence in context: A187560 A338818 A290721 * A294052 A089130 A081340

Adjacent sequences:  A205529 A205530 A205531 * A205533 A205534 A205535

KEYWORD

nonn

AUTHOR

M. F. Hasler, Jan 28 2012

STATUS

approved

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Last modified December 6 06:14 EST 2021. Contains 349563 sequences. (Running on oeis4.)