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a(n) is the least inverse of A071542, i.e., minimal i such that A071542(i) = n.
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%I #23 Jul 17 2017 02:17:18

%S 0,1,2,4,6,8,10,12,16,18,20,24,28,32,34,36,40,44,48,52,56,60,64,66,68,

%T 72,76,80,84,88,92,96,100,104,108,112,116,120,126,128,130,132,136,140,

%U 144,148,152,156,160,164,168,172,176,180,184,190,192,196,200,204,208,212,216,222,226,232,238,244,250,256,258,260,264,268,272,276

%N a(n) is the least inverse of A071542, i.e., minimal i such that A071542(i) = n.

%C Also the positions in A071542 where new records appear, record values appearing in the ascending order, i.e., as A001477 (because A071542 is a monotone and surjective function).

%H Antti Karttunen, <a href="/A213708/b213708.txt">Table of n, a(n) for n = 0..16500</a>

%t Function[s, Map[FirstPosition[s, #] &, Union@ s]]@ Table[-1 + Length@ NestWhileList[# - DigitCount[#, 2, 1] &, n, # > 0 &], {n, 276}] // Flatten (* _Michael De Vlieger_, Jul 16 2017 *)

%o (Scheme with _Antti Karttunen_'s intseq-additions): (define A213708 (RECORD-POS 0 0 A071542))

%Y Cf. A173601 for the greatest inverse. A086876 gives the first differences.

%Y Cf. A179016, A213730.

%K nonn

%O 0,3

%A _Antti Karttunen_, Oct 24 2012