369 (number)

← 368 369 370 →
Cardinalthree hundred sixty-nine
Ordinal369th
(three hundred sixty-ninth)
Factorization32 × 41
Divisors1, 3, 9, 41, 123, 369
Greek numeralΤΞΘ´
Roman numeralCCCLXIX
Binary1011100012
Ternary1112003
Senary14136
Octal5618
Duodecimal26912
Hexadecimal17116

369 (three hundred [and] sixty-nine) is the natural number following 368 and preceding 370.

In mathematics

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369 is the magic constant of the 9 × 9 magic square[1][2] and the n-Queens Problem for n = 9.[2]

There are 369 free octominoes (polyominoes of order 8).[3][4]

369 is a Ruth-Aaron Pair with 370. The sums of their prime factors are equivalent.[5]

References

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  1. ^ Kraitchik, M (1942). "Magic Squares". Mathematical Recreations. New York: Norton. pp. 142–192.
  2. ^ a b Sequence A006003 in OEIS.
  3. ^ Redelmeier, D. Hugh (1981). "Counting polyominoes: yet another attack". Discrete Mathematics. 36 (2): 191–203. doi:10.1016/0012-365X(81)90237-5.
  4. ^ Sequence A000105 in OEIS.
  5. ^ "Ruth-Aaron Pair". mathworld.wolfram.com.