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 A109326 Smallest positive number that requires n steps to be represented as a sum of palindromes using the greedy algorithm. 3
 1, 10, 21, 1022, 101023, 1000101024 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Index of first occurrence of n in A088601. Presumably this sequence is unbounded. - N. J. A. Sloane, Aug 28 2015 The greedy algorithm means iteration of A261424 until a palindrome is reached. For n = 3, 4, ... we have a(n+1) = 10^L(n) + a(n) + 1 with L(n) = 2^(n-2) + 1 = length(a(n))*2 - 3 for n > 3. We have a(7) <= 10^17 + 1000101025, a(8) <= 10^33 + 10^17 + 1000101026, a(9) <= 10^65 + 10^33 + 10^17 + 1000101027, a(10) <= 10^129 + 10^65 + 10^33 + 10^17 + 1000101028, etc, with conjectured equality. - M. F. Hasler, Sep 08 2015, edited Sep 09 2018 LINKS Table of n, a(n) for n=1..6. M. F. Hasler, Sum of palindromes, OEIS wiki, Sept. 2015. FORMULA a(n) = Sum_{0 <= k <= n-3} 10^(2^k+1) + n - 82, for n > 2 (conjectured). - M. F. Hasler, Sep 08 2015 PROG (Python) # uses functions in A088601 def afind(limit): record = 0 for i in range(1, limit+1): steps = A088601(i) if steps > record: print(i, end=", "); record = steps afind(10**6) # Michael S. Branicky, Jul 12 2021 CROSSREFS Cf. A088601, A002113, A261422, A261423. Sequence in context: A041198 A035318 A039821 * A369120 A080454 A226789 Adjacent sequences: A109323 A109324 A109325 * A109327 A109328 A109329 KEYWORD nonn,base,more AUTHOR David Wasserman, Aug 11 2005 EXTENSIONS Edited by N. J. A. Sloane, Aug 28 2015 STATUS approved

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Last modified July 20 12:30 EDT 2024. Contains 374445 sequences. (Running on oeis4.)