Dave Kreskowiak wrote:Wrong again! 100 : 511247092564 Exactly this time ! Regards, R

After a bit more fiddling:

Test length 48 th : 526646 526,646
Test length 49 th : 686646 686,646
Test length 50 th : 894810 894,810
51st length : 1,166,642
52nd length : 1,521,070
53rd length : 1,983,164
54th length : 2,585,639
55th length : 3,371,142
56th length : 4,395,278
57th length : 5,730,540
58th length : 7,471,449
59th length : 9,741,236
60th length : 12,700,573
61st length : 16,558,941
62nd length : 21,589,461
63rd length : 28,148,228
64th length : 36,699,513
65th length : 47,848,635
66th length : 62,384,802
67th length : 81,336,981
68th length : 106,046,733
69th length : 138,263,181
70th length : 180,266,818
71st length : 235,030,941
72nd length : 306,432,122
73rd length : 399,524,610
74th length : 520,898,113
75th length : 679,144,257
76th length : 885,464,758
77th length : 1,154,464,356
78th length : 1,505,184,637
79th length : 1,962,451,918
80th length : 2,558,634,627
81st length : 3,335,934,550
82nd length : 4,349,374,155
83rd length : 5,670,691,453
84th length : 7,393,418,089
85th length : 9,639,500,137
86th length : 12,567,930,256
87th length : 16,386,002,249
88th length : 21,363,984,700
89th length : 27,854,252,387
90th length : 36,316,229,718
91st length : 47,348,911,849
92nd length : 61,733,265,560
93rd length : 80,487,511,283
94th length : 104,939,199,534
95th length : 136,819,183,789
96th length : 178,384,141,824
97th length : 232,576,318,416
98th length : 303,231,797,036
99th length : 395,352,043,407
100th length : 515,457,942,582

Regards , R

340472211484 approx (via log extrapolation)