A030480 Primes with property that when squared all even digits occur together and all odd digits occur together.
2, 3, 5, 7, 17, 29, 47, 53, 67, 79, 83, 149, 151, 157, 257, 283, 457, 653, 683, 907, 1429, 1571, 1693, 1699, 2017, 2459, 2467, 2543, 2609, 2617, 2843, 2879, 2909, 2971, 4759, 5101, 5179, 5333, 6653, 6803, 6947, 6949, 7759, 8297, 9091, 9103
Offset: 1
Links
- Robert Israel, Table of n, a(n) for n = 1..1000
Programs
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Maple
filter:= proc(n) local L; if not isprime(n) then return false fi; convert(convert(n^2,base,10)[2..-1] mod 2,set) = {0}; end proc: filter(2):= true: filter(3):= true: select(filter, [2,seq(i,i=3..10000,2)]); # Robert Israel, Oct 17 2023 -
Mathematica
With[{upto=10^4},Select[Prime[Range[upto]],Count[IntegerDigits[#^2],?OddQ]<2&]] (* _Paolo Xausa, Oct 18 2023 *)
Extensions
Offset changed by Robert Israel, Oct 17 2023
Comments