## A278935 ## Entries a(40)=a(80)= -1 are speculative. ## if the corresponding numbers exist, they must be larger than 10^50 2 126 3 84 4 63 5 3231 6 42 7 4154 8 2143 9 1143 10 4105263158 11 6440909347642 12 21 13 11 14 2077 15 1077 16 18063 17 1206 18 16056 19 105882353 20 2052631579 21 43304763 22 3220454673821 23 8044 24 12042 25 30411 26 6039 27 5037593985 28 321603571507896 29 5035 30 14033492823 31 3033 32 17403126122889 33 20713030303119 34 603 35 12028708134 36 8028 37 40274 38 526315802631579 39 4026 40 -1 41 221730243903 42 476202381 43 31792023255848 44 2390022727705 45 3022556391 46 4022 47 4255320212766 48 6021 49 112020415603353992 50 3780200021166261 51 402 52 102019238023387401 53 490076018867926 54 132460185185703 55 1912018182164 56 160801785753948 57 159490175439 58 313480172414 59 17017 60 634016667543 61 48016404648 62 8016194332 63 6501588077205 64 4015748031496062992126 65 6301539213291 66 37186195001515151515275 67 4015037594 68 267380147059 69 40146 70 6014354067 71 134780014084510 72 4014 73 553201369869798 74 20137 75 10137 76 11441647601315789474 77 920129906806 78 2013 79 1013 80 -1 81 3012448132780083 82 6820121955581 83 3012145749 84 107201190502632 85 301185770751 86 15896011627924 87 6401149838304 88 158932011363638 89 9201123870022 90 209201111122914 91 4501099438065 92 2011 93 1011 94 2127660106383 95 33010533035429301 96 5801042040963 97 10299010309299 98 56010207801676996 99 16010101011375609633 100 1618010000123610922261091