sum(4,17) = 147 = 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17
sum(1,20) = 210
sum(19,59) = 1599
sum(22,77) = 2772
sum(20,156) = 12056
sum(34,167) = 13467
sum(23,211) = 22113
sum(79,227) = 22797
sum(84,229) = 22849
sum(61,236) = 26136
sum(199,599) = 159999
sum(203,771) = 277103
sum(222,777) = 277722
sum(266,778) = 267786
sum(277,797) = 279777
sum(145,1520) = 1145520
sum(117,1522) = 1152217
sum(149,1525) = 1152549
sum(167,1527) = 1152767
sum(208,1568) = 1208568
sum(334,1667) = 1334667
sum(540,1836) = 1540836
sum(315,1990) = 1931590
sum(414,2062) = 2041462
sum(418,2063) = 2041863
sum(158,2083) = 2158083
sum(244,2132) = 2244132
sum(554,2139) = 2135549
sum(902,2347) = 2349027
sum(883,2558) = 2883558
sum(989,2637) = 2989637
sum(436,2963) = 4296336
sum(503,3303) = 5330303
sum(626,3586) = 6235866
sum(816,4183) = 8418316
sum(1075,4700) = 10470075
sum(1117,4922) = 11492217
sum(1306,5273) = 13052736
sum(1377,5382) = 13538277
sum(1420,5579) = 14557920
sum(1999,5999) = 15999999
sum(2727,7272) = 22727727
sum(2516,7528) = 25175286
sum(2625,7774) = 26777425
sum(2222,7777) = 27777222
sum(3765,9490) = 37949065
sum(535,10319) = 53103195
sum(1101,14973) = 111497301
sum(2088,15688) = 120885688
sum(3334,16667) = 133346667
sum(2603,19798) = 192603798
sum(3093,19893) = 193093893
sum(1162,20039) = 200116239
sum(1415,20095) = 200914155
sum(1563,20118) = 201156318
sum(2707,20294) = 202270794
sum(2518,20318) = 203251818
sum(2608,20333) = 203326083
sum(2895,20370) = 203289570
sum(3424,20552) = 205342452
sum(4255,20855) = 208425555
sum(4571,20971) = 209457171
sum(4613,21028) = 210461328
sum(4742,21259) = 214742259
sum(6318,21798) = 217631898
sum(6498,21943) = 219649843
sum(7080,22305) = 223708005
sum(7243,22358) = 223724358
sum(6833,22368) = 226833368
sum(7128,22473) = 227128473
sum(4523,22603) = 245232603
sum(4978,22898) = 249782898
sum(8339,23019) = 230183399
sum(8610,23191) = 231861091
sum(6013,23588) = 260133588
sum(9252,23652) = 236925252
sum(6488,23913) = 264883913
sum(8379,25254) = 283795254
sum(4012,28667) = 402866712
sum(4922,31762) = 492317622
sum(4998,31801) = 493180198
sum(5200,32675) = 520326750
sum(7707,40092) = 774009207
sum(7868,40431) = 786404318
sum(9325,44450) = 944450325
sum(11047,48287) = 1104828747
sum(14699,56100) = 1465610099
sum(16235,59860) = 1659860235
sum(19999,59999) = 1599999999
sum(17264,61239) = 1726123964
sum(17405,61605) = 1746160505
sum(18457,63782) = 1863782457
sum(25016,75028) = 2501750286
sum(28022,79942) = 2802799422
sum(37060,93740) = 3706937400
sum(7567,119567) = 7119567567
sum(9638,135513) = 9135513638
sum(15392,152607) = 11526075392
sum(17744,152880) = 11528807744
sum(12012,156387) = 12156387012
sum(20888,156888) = 12088856888
sum(30663,164538) = 13066364538
sum(33334,166667) = 13333466667
sum(36038,168838) = 13603868838