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A030480 Primes with property that when squared all even digits occur together and all odd digits occur together. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Primes whose squares have at most one odd digit. - Robert Israel, Oct 17 2023
LINKS
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 *)
CROSSREFS
Sequence in context: A178382 A360591 A289757 * A048418 A074788 A262833
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
Offset changed by Robert Israel, Oct 17 2023
STATUS
approved

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Last modified June 21 10:19 EDT 2024. Contains 373543 sequences. (Running on oeis4.)