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 A242437 Numbers not appearing in the sequence of integers, beginning with 1, that can be formed by adding any digit of any previous term to that previous term. 0
 3, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 21, 23, 25, 27, 29, 31, 43, 47, 51, 65, 71, 87, 95 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Is this sequence finite?  Any additional term > 10^8. If we start with an integer other than 1, different sequences appear.  3, 5, and 7 appear in none of these sequences starting with any n less than the integer in question.  Are there any other integers, like 3, 5, and 7, that do not appear in any sequence starting with n less than the integer in question? This sequence includes all terms from A241175 plus additional terms that cannot be made from the terms that are included in A241175. LINKS EXAMPLE 17 is not in this sequence because 1+1=2, 2+2=4, 4+4=8, 8+8=16, 16+1=17. 39 is not in this sequence because 1+1=2, 2+2=4, 4+4=8, 8+8=16, 16+6=22, 22+2=24, 24+4=28, 28+8=36, 36+3=39. 23 is in this sequence because there is no way to start at 1 and arrive at 23. (See A241175 for definition difference.) PROG (Python) complete = [] complete.append(1) complete.append(2) complete.append(4) complete.append(8) final = [] for a in range(2, 10000000):#search through 10^8 ....b = str(a) ....for c in reversed(range(1, 10)):#search the previous 9 integers ........d = str(a-c) ........if a - c in complete[-9:] and str(c) in d: ............complete.append(a)#this number can be made by digit addition ............break ........if c == 1:#If all 9 attempts fail ............final.append(a)#This is a member of the new sequence print(final) CROSSREFS Cf. A241175. Sequence in context: A308468 A213199 A184987 * A188916 A276278 A277727 Adjacent sequences:  A242434 A242435 A242436 * A242438 A242439 A242440 KEYWORD nonn,easy,base AUTHOR David Consiglio, Jr., May 13 2014 STATUS approved

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Last modified October 15 17:45 EDT 2021. Contains 348033 sequences. (Running on oeis4.)