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A052074 Squares of primes p^2 with the property that nextprime(p) is a substring of p^2. 4
529, 6889, 12769, 1261129, 40001200009, 107667328129, 145381301521, 510649971459777361, 24172491655282243145798689 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

a(n) = A052073(n)^2. - Paolo P. Lava, May 23 2018

EXAMPLE

The corresponding primes p are 23, 83, 113, 1123, 200003, 328127, ..., the "next primes" are 29, 89, 127, 1129, 200009, 328129, ..., and these numbers are indeed substrings of 529, 6889, 12769, 1261129, 40001200009, 107667328129, ...

MATHEMATICA

Select[Prime[Range[37*10^6]]^2, SequenceCount[IntegerDigits[#], IntegerDigits[ NextPrime[ Sqrt[#]]]]>0&] (* The program uses the SequenceCount function from Mathematica version 10 *) (* Harvey P. Dale, Jul 13 2016 *)

CROSSREFS

Cf. A052073, A052075, A052076, A274932.

Sequence in context: A082409 A066742 A067475 * A112079 A156573 A034987

Adjacent sequences:  A052071 A052072 A052073 * A052075 A052076 A052077

KEYWORD

nonn,base,more,nice

AUTHOR

Patrick De Geest, Jan 15 2000

EXTENSIONS

a(8) from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Sep 04 2006

Definition clarified and offset changed by N. J. A. Sloane, Jul 13 2016

a(9) from Giovanni Resta, May 24 2018

STATUS

approved

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Last modified May 20 02:50 EDT 2019. Contains 323412 sequences. (Running on oeis4.)