305

305 = 5 × 61

305 = 12 × 3 × 4 + 5 + 67 + 89

305 = 98 + 7 × 6 + 54 × 3 + 2 + 1

305 = 0^4 + 1^8 + 2^6 − 3^9 + 4^7 + 5^5 + 6^1 + 7^3 + 8^2 + 9^0

305 = 4^2 + 17^2 = 7^2 + 16^2

305^2 = 136^2 + 273^2 = 207^2 + 224^2

305 divides 11^4 - 1.

305 = (11 × 111 − 1)/(1 + 1 + 1 + 1)

305 = (2 + 2/2)⁽²⁺²⁾ + 222 + 2

305 = 333 − 3³ − 3/3

305 = 4⁴ + 44 + 4 + 4/4

305 = 5 × (55 + 5) + 5

305 = (6 − 6/6) × (66 − 6 + 6/6)

305 = 7 × (7 × 7 − 7) + 77/7

305 = (8 + 8) × (8 + 88/8) + 8/8

305 = (9 + 9) × (9 + 9) − 9 − 9 − 9/9

5th (n=4) Hexagonal prism number \((n+1)(3n^{2}+3n+1),\)

305 = n + (n+1)^2 (n=16)

305 = a(n) = n-th prime + n.

Hypotenuse of primitive Pythagorean triangle (x^2 + y^2 where × is even, y is odd and gcd(x, y)=1).

Order all numbers from 1 to 305 so that the sum of 2 neighbors is a cube.

256, 87, 129, 214, 298, 45, 171, 172, 44, 299, 213, 130, 86, 257, 255,
88, 128, 215, 297, 46, 170, 173, 43, 300, 212, 131, 85, 258, 254, 89, 127, 216, 296,
47, 169, 174, 42, 301, 211, 132, 84, 259, 253, 90, 126, 217, 295, 48, 168, 175, 41, 302,
210, 133, 83, 260, 252, 91, 125, 218, 294, 49, 167, 176, 40, 303, 209, 134, 82, 261, 251,
92, 33, 183, 160, 56, 287, 225, 118, 98, 245, 267, 76, 140, 203, 13, 14, 202, 141, 75, 268,
244, 99, 26, 190, 153, 63, 280, 232, 111, 105, 238, 274, 69, 147, 196, 20, 7, 1, 124, 219,
293, 50, 166, 177, 39, 304, 208, 135, 81, 262, 250, 93, 32, 184, 159, 57, 286, 226, 117, 8,
19, 197, 146, 70, 273, 239, 104, 112, 231, 281, 62, 154, 189, 27, 37, 179, 164, 52, 291, 221,
122, 3, 5, 22, 194, 149, 67, 276, 236, 107, 109, 234, 278, 65, 151, 192, 24, 101, 242, 270,
73, 143, 200, 16, 11, 205, 138, 78, 265, 247, 96, 120, 223, 289, 54, 162, 181, 35, 29, 187,
156, 60, 283, 229, 114, 102, 241, 271, 72, 144, 199, 17, 108, 235, 277, 66, 150, 193, 23,
4, 121, 222, 290, 53, 163, 180, 36, 28, 188, 155, 61, 282, 230, 113, 103, 240, 272, 71, 145,
198, 18, 9, 116, 227, 285, 58, 158, 185, 31, 94, 249, 263, 80, 136, 207, 305, 38, 178, 165,
51, 292, 220, 123, 2, 6, 21, 195, 148, 68, 275, 237, 106, 110, 233, 279, 64, 152, 191, 25,
100, 243, 269, 74, 142, 201, 15, 12, 204, 139, 77, 266, 246, 97, 119, 224, 288, 55, 161,
182, 34, 30, 186, 157, 59, 284, 228, 115, 10, 206, 137, 79, 264, 248, 95

(256 + 87) = 343 = 7*7*7

(87 + 129) = 216 = 6*6*6

etc...

Number of ordered pairs of integers (x,y) with x^2+y^2 < 10^2

Semiprime (Product of 2 Primes)

Factors: 1, 5, 61, 305

Three hundred five

Representations, Binary to Hexadecimal:

100110001_2
102022_3
10301_4
2210_5
1225_6
614_7
461_8
368_9
258_11
215_12
1a6_13
17b_14
155_15
131_16

304 <--- ---> 306