login
A267430
Squares whose digit sum is not a prime.
1
0, 1, 4, 9, 36, 64, 81, 100, 121, 144, 169, 196, 225, 324, 361, 400, 441, 484, 529, 576, 729, 900, 961, 1089, 1225, 1296, 1521, 1681, 1764, 1849, 2025, 2116, 2304, 2601, 2916, 3025, 3249, 3364, 3481, 3600, 3969, 4356, 4489, 4624, 4761, 5041, 5184, 5476, 5625
OFFSET
1,3
COMMENTS
Complement of A065408.
Includes A016766. - Robert Israel, Jan 15 2016
LINKS
MAPLE
remove(t->isprime(convert(convert(t, base, 10), `+`)), [seq(i^2, i=0..100)]); # Robert Israel, Jan 15 2016
MATHEMATICA
Select[Range[0, 100]^2, ! PrimeQ[Total[IntegerDigits[#]]] &]
PROG
(Magma) [n^2: n in [0..80] | not IsPrime(&+Intseq(n^2))];
(PARI) is(n) = issquare(n) && !ispseudoprime(sumdigits(n)); \\ Altug Alkan, Jan 15 2016
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Vincenzo Librandi, Jan 15 2016
EXTENSIONS
a(1)=0 prepended by Altug Alkan Jan 15 2016
Edited by Bruno Berselli, Jan 15 2016
STATUS
approved