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Talk:Trivial topology

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Oops, you're right. In the original statement I spoke of limit points of S in S, which worked when it was empty, but not currently. I added the statement about infinite subsets having limit points because this is the definition of limit point compactness (in some texts), and is an important property
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The second is not correct. Given a singleton S={s}, s is not a limit point of S, because it does not lie in the closure of S-{s}, which is empty. It can still be generalized somewhat, however. I changed it to this, maybe the language could be cleaned up some:
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Given a subset S of X which is not a singleton, all elements of X are limit points of S. If S is a singleton, every point of X \ S is still a limit point of S. In particular, every infinite subset of X has a limit point.
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Yup you're right, except that your version doesn't work when S is empty. I also don't see the point of the last statement about infinite sets: you don't need infinitely many elements, you only need two.
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of metric compact spaces. If there were a page on limit point compactness I'd link to that instead.
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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To AxelBoldt: most of your changes were good, but you changed this line:
174:. In particular, every infinite subset of X has a limit point. 15: 101:, a collaborative effort to improve the coverage of 8: 166:Given a subset S of X, an element of S is a 19: 47: 49: 7: 95:This article is within the scope of 38:It is of interest to the following 14: 257:Low-priority mathematics articles 115:Knowledge:WikiProject Mathematics 252:Start-Class mathematics articles 118:Template:WikiProject Mathematics 82: 72: 51: 20: 170:of S if and only if S is not a 135:This article has been rated as 186:has more than one element and 1: 109:and see a list of open tasks. 190:is some non-empty subset of 273: 239:00:28, 30 Nov 2003 (UTC) 229:16:18, 29 Nov 2003 (UTC) 221:15:52, 29 Nov 2003 (UTC) 134: 67: 46: 141:project's priority scale 194:, then each element of 98:WikiProject Mathematics 28:This article is rated 121:mathematics articles 90:Mathematics portal 34:content assessment 155: 154: 151: 150: 147: 146: 264: 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 272: 271: 267: 266: 265: 263: 262: 261: 242: 241: 237:Derrick Coetzee 219:Derrick Coetzee 160: 120: 117: 114: 111: 110: 88: 81: 61: 32:on Knowledge's 29: 12: 11: 5: 270: 268: 260: 259: 254: 244: 243: 208: 207: 176: 175: 159: 158:Recent changes 156: 153: 152: 149: 148: 145: 144: 133: 127: 126: 124: 107:the discussion 94: 93: 77: 65: 64: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 269: 258: 255: 253: 250: 249: 247: 240: 238: 234: 230: 228: 222: 220: 216: 212: 205: 201: 197: 193: 189: 185: 181: 180: 179: 173: 169: 165: 164: 163: 157: 142: 138: 132: 129: 128: 125: 108: 104: 100: 99: 91: 85: 80: 78: 75: 71: 70: 66: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 235: 231: 223: 217: 213: 209: 203: 195: 191: 187: 183: 177: 161: 137:Low-priority 136: 96: 62:Low‑priority 40:WikiProjects 200:limit point 168:limit point 112:Mathematics 103:mathematics 59:Mathematics 30:Start-class 246:Categories 227:AxelBoldt 178:to this: 172:singleton 139:on the 36:scale. 198:is a 202:of 182:If 131:Low 248:: 206:. 204:S 196:X 192:X 188:S 184:X 143:. 42::

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