This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A276326 #29 Sep 01 2016 10:54:15 %S A276326 0,1,2,3,10,11,12,13,20,21,22,23,30,31,32,33,40,41,100,101,102,103, %T A276326 110,111,112,113,120,121,122,123,130,131,132,133,140,141,200,201,202, %U A276326 203,210,211,212,213,220,221,222,223,230,231,232,233,240,241,300,301,302,303,310,311,312,313,320,321,322,323,330,331,332,333,340,341,400 %N A276326 Numbers expressed in greedy A001563-base. %C A276326 Terms A001563(1) = 1, A001563(2) = 4, A001563(3) = 18, ... give the base values for the digit positions from 1 onward. Digit places are filled by always trying to find the largest possible term of A001563 that still fits into the sum. %C A276326 A130744(8) = 3225600 = 10*A001563(8) is the first number which yields an ambiguous representation when expressed in decimal, because in this base it is actually "A0000000" (where digit "A" stands for ten). %H A276326 Antti Karttunen, <a href="/A276326/b276326.txt">Table of n, a(n) for n = 0..4320</a> %e A276326 To recover n from a(n) the digits in positions i = 1, 2, 3, ... (starting indexing from the least significant digit at right) are multiplied by A001563(i) and added together: %e A276326 ---------------- %e A276326 n a(n) %e A276326 ---------------- %e A276326 0 0 %e A276326 1 1 %e A276326 2 2 %e A276326 3 3 %e A276326 4 10 %e A276326 5 11 %e A276326 6 12 %e A276326 7 13 %e A276326 8 20 %e A276326 9 21 %e A276326 10 22 %e A276326 11 23 %e A276326 12 30 %e A276326 13 31 %e A276326 14 32 %e A276326 15 33 %e A276326 16 40 %e A276326 17 41 (as 4*A001563(2) + 1*A001563(1) = 17) %e A276326 18 100 (as 1*A001563(3) + 0*A001563(2) + 0*A001563(1) = 18) %e A276326 and: %e A276326 3225599 99111111 (as 3225599 = 9*b(8) + 9*b(7) + b(6) + b(5) + b(4) + b(3) + b(2) + b(1)), where b(n) = A001563(n). %t A276326 f[n_] := Block[{a = {{0, n}}}, Do[AppendTo[a, {First@ #, Last@ #} &@ QuotientRemainder[a[[-1, -1]], (# #!) &[# - i]]], {i, 0, # - 1}] &@ NestWhile[# + 1 &, 0, (# #!) &[# + 1] <= n &]; Rest[a][[All, 1]]]; Table[FromDigits@ f@ n, {n, 72}] (* _Michael De Vlieger_, Aug 31 2016 *) %o A276326 (Scheme) %o A276326 (define (A276326 n) (let loop ((n n) (s 0)) (if (zero? n) s (let ((dig (A276333 n))) (if (> dig 9) (error "A276326: ambiguous representation of n, digit > 9 would be needed: " n dig) (loop (A276335 n) (+ s (* dig (expt 10 (- (A258198 n) 1)))))))))) %Y A276326 Cf. A001563, A130744, A258198, A276335. %Y A276326 Cf. A276327 (the least significant nonzero digit). %Y A276326 Cf. A276328 (the sum of digits). %Y A276326 Cf. A276333 (the most significant digit). %Y A276326 Cf. A276336 (a largest digit). %Y A276326 Cf. A276337 (number of nonzero digits). %Y A276326 Cf. A033312 (repunits). %Y A276326 Cf. A276091 (no digits larger than one). %Y A276326 Differs from A007090 for the first time at n=16 and from A055655 at n=18. %Y A276326 Cf. also A007623, A007961, A000433, A014418, A265747. %K A276326 nonn,base %O A276326 0,3 %A A276326 _Antti Karttunen_, Aug 30 2016