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k such that A035312(k-1) = n or 0 if there is none.
6

%I #28 May 25 2024 14:36:48

%S 1,2,3,4,11,5,7,16,6,22,8,12,17,29,37,56,9,23,46,67,79,92,13,30,18,10,

%T 106,137,38,121,24,172,154,47,57,68,211,191,232,14,80,31,93,254,277,

%U 326,352,19,107,596,301,436,39,379,407,25,122,138,466,529,155,497,48

%N k such that A035312(k-1) = n or 0 if there is none.

%C At least up through the first 19 terms (ending at 46), this appears to be identical to the inverse of sequence A035312 considered as a permutation of the positive integers. - _Howard A. Landman_, Sep 23 2001

%C This sequence is *by definition* the inverse of A035312 (upon shifting its offset), provided that A035312 indeed is surjective on the positive integers. - _M. F. Hasler_, May 09 2013

%H Reinhard Zumkeller, <a href="/A035358/b035358.txt">Table of n, a(n) for n = 1..1000</a>

%H A. C. Zorach, <a href="http://www.cazort.net/static/triangle.php">Additive triangle</a>

%H Reinhard Zumkeller, <a href="/A035312/a035312_2.hs.txt">Haskell programs for sequences in connection with Zorach additive triangle</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%F a(n) = A000217(A072039(n) - 1) + A072038(n) if the sequence is in fact the inverse permutation of the flattened Zorach additive triangle. - _Reinhard Zumkeller_, Apr 30 2011

%o (Haskell) -- See link for Haskell program.

%Y Cf. A035311, A035312, A035313.

%K nonn

%O 1,2

%A _Christian G. Bower_, Nov 15 1998