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A145742 Composite numbers n such that all 10 numbers n+4*m^2 for m=1,2,...,10 are prime. 2
143473, 2821813, 3171877, 27439003, 95771533, 107832187, 174499873, 315915517, 438561313, 761271373, 1010315923, 1083101167, 1247119687, 1272171217, 1494582637, 1540272427, 2760699643, 3205014607, 3615583147, 3636010807 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There is no further term up to 2*10^8.

LINKS

Table of n, a(n) for n=1..20.

EXAMPLE

174499873 is composite and all 10 numbers 174499873+4m^2 for m=1,2,...,10 are prime.

MATHEMATICA

Select[Range[140001, 364*10^7, 2], CompositeQ[#]&&AllTrue[#+{4, 16, 36, 64, 100, 144, 196, 256, 324, 400}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jun 12 2017 *)

CROSSREFS

Cf. A145741, A145743.

Sequence in context: A146754 A180340 A004042 * A236995 A204641 A133324

Adjacent sequences:  A145739 A145740 A145741 * A145743 A145744 A145745

KEYWORD

nonn

AUTHOR

Farideh Firoozbakht, Oct 17 2008

EXTENSIONS

a(8)-a(20) from Donovan Johnson, Nov 17 2008

STATUS

approved

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Last modified September 25 15:27 EDT 2021. Contains 347658 sequences. (Running on oeis4.)