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A178811 The smallest integer that begins the largest run of consecutive integers with the prime signature of A025487(n). 1
1, 2, 4, 33, 8, 10093613546512321, 16, 28375, 1309, 32, 36, 7939375, 932537185321, 64 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

From Bernard Schott, Feb 17 2021: (Start)

The corresponding lengths of these largest runs of consecutive integers are in A178810.

If a(n) = 2^k for some k <> 1, then a(n) = A025487(n) and A178810(n) = 1; for k = 1, a(2) = A025487(2) = A178810(2) = 2 because there exists a run of two consecutive primes (2,3).

a(17) = 203433, a(18) = 128. (End)

LINKS

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

Diophante, A1845, Les squelettes (in French).

EXAMPLE

For n = 3, A025487(3) = 4, corresponding to a prime signature of {2}. Since the maximum number of consecutive integers with that prime signature is 1, a(3) is 4, the smallest integer that starts a "run" of 1.

A025487(4) = 6 whose prime signature is {1,1}; a(4) = 33 because 33 is the smallest integer where starts a run of A178810(4) = 3 consecutive integers with prime signature {1,1}: (33=3*11, 34=2*17, 35=5*7). - Bernard Schott, Feb 16 2021

CROSSREFS

Cf. A025487, A178810 (maximum size of such runs), A141621.

Sequence in context: A073888 A114642 A200980 * A099433 A051225 A306582

Adjacent sequences:  A178808 A178809 A178810 * A178812 A178813 A178814

KEYWORD

more,nonn

AUTHOR

Will Nicholes, Jun 16 2010

EXTENSIONS

Minor edits by Ray Chandler, Jul 29 2010

a(6) corrected by Bobby Jacobs, Sep 25 2016

a(12) from Hugo van der Sanden, May 20 2019

a(13)-a(14) from Bernard Schott, Feb 16 2021

STATUS

approved

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Last modified November 27 03:56 EST 2021. Contains 349345 sequences. (Running on oeis4.)