Let's take triplets of primes, starting with 2, 3 and 5, and find three consecutive numbers (let's call them \(k, k+1\) and \(k+3\)) that are divisible by these primes respectively. In other words, we need \(k\) to be a multiple of 2, \(k+1\) to be a multiple of 3 and \(k+2\) to be a multiple of 5. A little trial error shows that the value of \(k\) that satisfies is 8 because 2 divides 8, 3 divides 9 and 5 divides 10. This triplet of numbers (8, 9 and 10) is the smallest that is divisible by 2, 3 and 5 respectively. As the primes get larger however, we need an algorithm to find the values of \(k, k+1\) and \(k+2\) that are divisible by consecutive primes \(p, q\) and \(r\). Here is the permalink to an algorithm that will do just that. The results are shown below.
prime 1 prime 2 prime 3 number 1 number 2 number 3
2 3 5 8 9 10
3 5 7 54 55 56
5 7 11 20 21 22
7 11 13 791 792 793
11 13 17 1936 1937 1938
13 17 19 169 170 171
17 19 23 4046 4047 4048
19 23 29 114 115 116
23 29 31 9453 9454 9455
29 31 37 31929 31930 31931
31 37 41 23901 23902 23903
37 41 43 2664 2665 2666
41 43 47 44977 44978 44979
43 47 53 65188 65189 65190
47 53 59 122482 122483 122484
53 59 61 134991 134992 134993
59 61 67 170982 170983 170984
61 67 71 220027 220028 220029
67 71 73 101103 101104 101105
71 73 79 85555 85556 85557
73 79 83 27886 27887 27888
79 83 89 296724 296725 296726
83 89 97 629140 629141 629142
89 97 101 154326 154327 154328
97 101 103 546207 546208 546209
101 103 107 46864 46865 46866
103 107 109 950587 950588 950589
107 109 113 1043892 1043893 1043894
109 113 127 1548890 1548891 1548892
113 127 131 70738 70739 70740
127 131 137 702945 702946 702947
131 137 139 2389964 2389965 2389966
137 139 149 1513987 1513988 1513989
139 149 151 416305 416306 416307
149 151 157 3386174 3386175 3386176
151 157 163 3220226 3220227 3220228
157 163 167 1531221 1531222 1531223
163 167 173 2865051 2865052 2865053
167 173 179 4309602 4309603 4309604
173 179 181 3968966 3968967 3968968
179 181 191 826264 826265 826266
181 191 193 3557374 3557375 3557376
191 193 197 2119718 2119719 2119720
193 197 199 4096811 4096812 4096813
197 199 211 1823038 1823039 1823040
199 211 223 8583268 8583269 8583270
211 223 227 7453997 7453998 7453999
223 227 229 9175112 9175113 9175114
227 229 233 9590977 9590978 9590979
229 233 239 3294852 3294853 3294854
The number associated with my diurnal age today, 27886, appears in the above list and is associated with the primes 73, 79 and 83. Thus we have:$$ \begin{align} 27886 &= 2 \times \textbf{73} \times 191 \\ 27887 &= \textbf{79} \times 353 \\ 27888 &= 2^4 \times 3 \times 7 \times \textbf{83} \end{align} $$Figure 1 shows a plot of the prime 1 against number 1 with some annotations added. Though the trend of number 1's is upward, there is a lot of up and down along the way. The vertical axis of the graph is logarithmic.
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