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%I #42 Aug 17 2020 22:24:18
%S 0,24,2510,5210,8991,56384,348732,460719,867839,28997919,193889375,
%T 254181375,419321664,1018179999,2654951424,1297015971839,
%U 62061633644031
%N Bogotá numbers k such that k + 1 is also Bogotá number.
%C a(18) > 10^15 if it exists. - _David A. Corneth_, Aug 06 2020
%C From _Chai Wah Wu_, Aug 17 2020: (Start)
%C The following numbers are terms:
%C 2805402158142975 = 153931531311*(1*5*3*9*3*1*5*3*1*3*1*1) = 111822471227*(1*1*1*8*2*2*4*7*1*2*2*7) - 1.
%C 8748948067725824 = 2441112742111*(2*4*4*1*1*1*2*7*4*2*1*1*1) = 53339113353*(5*3*3*3*9*1*1*3*3*5*3) - 1.
%C (End)
%H Puzzling Stackexchange, <a href="https://puzzling.stackexchange.com/questions/98998/pairs-of-bogot%c3%a1-numbers?noredirect=1#comment281441_98998">Pairs of Bogotá numbers</a>, 2020.
%e n | a(n) a(n)+1
%e -----+------------------------------------------------------------------
%e 1 | 0 = 0 * 0 1 = 1 * 1
%e 2 | 24 = 12 * (1*2) 25 = 5 * 5
%e 3 | 2510 = 251 * (2*5*1) 2511 = 93 * (9*3)
%e 4 | 5210 = 521 * (5*2*1) 5211 = 193 * (1*9*3)
%e 5 | 8991 = 333 * (3*3*3) 8992 = 1124 * (1*1*2*4)
%e 6 | 56384 = 881 * (8*8*1) 56385 = 537 * (5*3*7)
%e 7 | 348732 = 3229 * (3*2*2*9) 348733 = 7117 * (7*1*1*7)
%e 8 | 460719 = 7313 * (7*3*1*3) 460720 = 11518 * (1*1*5*1*8)
%e 9 | 867839 = 17711 * (1*7*7*1*1) 867840 = 5424 * (5*4*2*4)
%e 10 | 28997919 = 119333 * (1*1*9*3*3*3) 28997920 = 51782 * (5*1*7*8*2)
%Y Cf. A336826.
%K nonn,more,base
%O 1,2
%A _Seiichi Manyama_, Aug 06 2020
%E a(11)-a(17) from _David A. Corneth_, Aug 06 2020
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