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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
OFFSET
1,1
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
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