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A278647
First differences of Hypotenuse numbers A009003.
1
5, 3, 2, 2, 3, 5, 1, 3, 1, 4, 1, 2, 2, 1, 1, 4, 5, 1, 1, 1, 2, 3, 2, 1, 4, 3, 2, 3, 1, 1, 3, 2, 2, 3, 2, 2, 1, 1, 4, 2, 3, 1, 1, 2, 1, 1, 3, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 5, 5, 1, 1, 3, 3, 2, 1, 2, 1, 1, 3, 2, 1, 1, 2, 1, 4, 1, 4, 1, 3, 1, 1, 3, 2, 1, 1, 1, 2, 2, 3, 3, 1, 1, 2, 3, 2, 1, 1, 1, 3
OFFSET
1,1
COMMENTS
a(n) <= 5, since A009003 contains all multiples of 5. - Robert Israel, Dec 08 2016
LINKS
FORMULA
a(n) = A009003(n+1) - A009003(n).
MAPLE
L:= select(t -> has(numtheory:-factorset(t) mod 4, 1), [$1..1000]):
L[2..-1]-L[1..-2]; # Robert Israel, Dec 08 2016
MATHEMATICA
Differences@ Select[Range@ 208, Length@ PowersRepresentations[#^2, 2, 2] > 1 &] (* Michael De Vlieger, Nov 25 2016, after Alonso del Arte at A009003 *)
CROSSREFS
Cf. A009003.
Sequence in context: A088324 A352153 A052038 * A249802 A249574 A090125
KEYWORD
nonn
AUTHOR
STATUS
approved