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A118126 Lucky numbers (A000959) at which records in first differences (A031883) occur. 0

%I

%S 1,3,15,51,171,745,1057,3507,23205,50779,51475,97113,241887,593727,

%T 636291,1661215,6010095,6100953,8825911,22032619,24058237,71730273,

%U 84577003,98797723,119871675,255510487,380154649,404917765,704823889,910302427,1696449051,2565189555,9024827079

%N Lucky numbers (A000959) at which records in first differences (A031883) occur.

%C An increasing subset of sequence A031884.

%e a(4) = 51 since the 4th record value in the lucky number "first differences" sequence occurs A031883(14) = 12 which corresponds to lucky number A000959(14) = 51.

%t lst = Range[1, 10^6, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; lst2 = {}; d = 0; Do[a = t[[n + 1]] - t[[n]]; If[a > d, d = a; AppendTo[lst, t[[n]]]], {n, 5286237}]; lst2

%Y Cf. A000959, A031883, A031884.

%K nonn,more,changed

%O 1,2

%A _Robert G. Wilson v_, May 12 2006

%E a(25)-a(29) from _Donovan Johnson_, Oct 23 2010

%E a(30) from _Donovan Johnson_, Jun 20 2011

%E a(31)-a(33) from _Kevin P. Thompson_, Nov 24 2021

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Last modified November 30 17:04 EST 2021. Contains 349424 sequences. (Running on oeis4.)