Problems & Puzzles: Puzzles

Puzzle 734. "Common Sigma, Uncommon Clique" Numbers

My friend Fred Schneider propose the following puzzle:

I have come across an interesting sequence while trying to solve a different problem.
I was wondering if any readers would like to try to extend it.

A239635 (I just submitted it so I think it's still being reviewed)


"Common Sigma, Uncommon Clique" Numbers 

The n-th term is the minimum number s where exists a set of n numbers which each have sigma = s (Common Sigma) and which are all relatively prime to each other (Uncommon Clique).

Here are the first 32 terms:
1, 12, 24, 72, 240, 360, 1440, 1440, 1440, 8640, 10080, 15120, 34560, 45360, 55440, 60480, 60480, 166320, 181440, 211680, 332640, 332640, 332640, 665280, 665280, 665280, 831600, 907200, 1663200, 2494800, 2661120, 2661120


And,  for the first 5 terms, here are the solutions sets (and member factors which show the sets are mutually relatively prime):


1) 1 :
1 = 1


2) 12 :
6 = 2 * 3
11 = 11


3) 24 :
14 = 2 * 7
15 = 3 * 5
23 = 23


4) 72 :
46 = 2 * 23
51 = 3 * 17
55 = 5 * 11
71 = 71


5) 240 :
135 = 3^3 * 5
158 = 2 * 79
203 = 7 * 29
209 = 11 * 19
239 = 239

and similar details on the last (32nd) term I have found:



32) 2661120 :
1126240 = 2^5 * 5 * 7039
1667601 = 3^3 * 13 * 4751
2306549 = 7 * 109 * 3023
2420407 = 11 * 139 * 1583
2498269 = 17 * 223 * 659
2514023 = 19 * 307 * 431
2534629 = 29 * 71 * 1231
2550217 = 23 * 110879
2550773 = 31 * 107 * 769
2566111 = 43 * 83 * 719
2572709 = 41 * 131 * 479
2599021 = 79 * 167 * 197
2605633 = 47 * 55439
2611787 = 53 * 49279
2616709 = 59 * 44351
2631463 = 89 * 29567
2640203 = 127 * 20789
2646157 = 179 * 14783
2647069 = 191 * 13859
2649793 = 239 * 11087
2650309 = 251 * 10559
2650777 = 263 * 10079
2654633 = 439 * 6047
2655337 = 503 * 5279
2657113 = 839 * 3167
2657177 = 863 * 3079
2657659 = 1151 * 2309
2657693 = 1187 * 2239
2657749 = 1259 * 2111
2657833 = 1439 * 1847
2657849 = 1511 * 1759
2661119 = 2661119

Q. Please send some more terms fo this sequence.


Contributions came from Fred Schneider

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Fred wrote:

Additional solutions:
 33) 3991680 
 34) 3991680 
 35) 4324320 
 36) 5765760 
 37) 6652800 
 38) 6652800 
 39) 6652800 
 40) 8648640 
 41) 9979200 
 42) 9979200 
 43) 9979200 
 44) 9979200 
 45) 9979200 
 46) 17297280 
 47) 21621600 
 48) 21621600 
 49) 28274400 
 51) 31600800 
 52) 31600800 
 55) 43243200 
 56) 64864800 
 57) 64864800 
 59) 64864800 
 64) 103783680 
 65) 103783680 

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