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A074817 Numbers n such that the number of primes between n^2 and (n+1)^2 = the number of primes between n and Reverse(n) (inclusive). 0
90, 102, 255, 306, 347, 357, 460, 850, 2274, 3430, 3620, 3908, 4038, 4140, 4309, 5050, 5650, 6040, 6840, 27320, 31336, 33076, 40130, 48140, 50130, 59340, 63340, 65440, 69250, 90270, 94660, 182010, 185773, 247105 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..34.

MATHEMATICA

Do[r = FromDigits[ Reverse[ IntegerDigits[n]]]; If[ PrimePi[(n + 1)^2] - PrimePi[n^2] == Abs[ PrimePi[n] - PrimePi[r]] + If[ Min[r, n] && PrimeQ[ Min[r, n]], 1, 0], Print[n]], {n, 1, 125000}]

CROSSREFS

Sequence in context: A088470 A147676 A045097 * A333745 A043224 A039401

Adjacent sequences:  A074814 A074815 A074816 * A074818 A074819 A074820

KEYWORD

nonn,base

AUTHOR

Jason Earls, Sep 08 2002

EXTENSIONS

Edited and extended by Robert G. Wilson v, Sep 12 2002

STATUS

approved

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Last modified October 30 03:24 EDT 2020. Contains 338076 sequences. (Running on oeis4.)