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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A333337 Indices of rows of n consecutive smallest primes in A333238, or -1 if n consecutive smallest primes do not appear in A333238.

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%I A333337 #10 Aug 29 2021 01:56:33
%S A333337 0,1,2,4,6,8,9,10,12,15,16,18,20,21,25,27,24,28,33,35,30,39,44,45,49,
%T A333337 51,55,63,57,65,69,75,77,81,85,60,76,87,91,95,99,105,111,115,117,119,
%U A333337 121,123,125,135,143,145,147,153,155,161,169,159,165,171,175,177
%N A333337 Indices of rows of n consecutive smallest primes in A333238, or -1 if n consecutive smallest primes do not appear in A333238.
%C A333337 Consider the irregular table where row m lists the distinct smallest primes p of prime partitions of m. Row n of this sequence contains all m that have n consecutive primes starting with 2.
%C A333337 Alternatively, positions of k-repunits in A333259.
%C A333337 A330507(n) = First terms in row n.
%C A333337 Null rows occur at n = {90, 151, 349, 352, 444, ...} and are thus filled with the term -1.
%e A333337 Table begins:
%e A333337        0:    0     1
%e A333337        1:    2     4
%e A333337        2:    6     8     9
%e A333337        3:   10    12    15    16
%e A333337        4:   18    20    21    25    27
%e A333337        5:   24    28    33    35
%e A333337        6:   30    39    44    45    49
%e A333337        7:   51    55    63
%e A333337        8:   57    65
%e A333337        9:   60    76    87    91    95
%e A333337       10:   69    75    77    81    85
%e A333337       11:   99   105
%e A333337       12:  111   115   117   119   121
%e A333337       13:  123   125   135
%e A333337       14:  143   145
%e A333337       15:  147   153   155   161   169
%e A333337       16:  159   165   171   175
%e A333337       17:  177   185   187
%e A333337 Consider the table plotting prime p in row m of A333238 at pi(p) place; intervening primes missing from row m are shown by "." as a place holder:
%e A333337     m      Primes in row m of A333238
%e A333337     ---------------------------------
%e A333337     2:     2
%e A333337     3:     .   3
%e A333337     4:     2
%e A333337     5:     2   .   5
%e A333337     6:     2   3
%e A333337     7:     2   .   .   7
%e A333337     8:     2   3
%e A333337     9:     2   3
%e A333337     10:    2   3   5
%e A333337     11:    2   3   .   .  11
%e A333337     12:    2   3   5
%e A333337     13:    2   3   .   .   .  13
%e A333337     14:    2   3   .   7
%e A333337     15:    2   3   5
%e A333337     16:    2   3   5
%e A333337     17:    2   3   5   .   .   .  17
%e A333337     ...
%e A333337 There are no primes in rows 0 or 1 of A333238, thus row 0 of this sequence contains {0, 1}.
%e A333337 The smallest prime, 2, appears alone in rows 2 and 4 of A333238, thus row 1 of this sequence contains {2, 4}.
%e A333337 We have the primes {2, 3} and no other primes in rows {6, 8, 9} in A333238, thus row 2 of this sequence contains {6, 8, 9}.
%e A333337 We have the primes {2, 3, 5} and no other primes in rows {10, 12, 15, 16} in A333238, thus row 3 of this sequence contains {10, 12, 15, 16}, etc.
%t A333337 Block[{m = 120, s, a}, a = ConstantArray[{}, m]; s = {Prime@ PrimePi@ m}; Do[If[# <= m, If[FreeQ[a[[#]], Last@ s], a = ReplacePart[a, # -> Union@ Append[a[[#]], Last@ s]], Nothing]; AppendTo[s, Last@ s], If[Last@ s == 2, s = DeleteCases[s, 2]; If[Length@s == 0, Break[], s = MapAt[Prime[PrimePi[#] - 1] &, s, -1]], s = MapAt[Prime[PrimePi[#] - 1] &, s, -1]]] &@ Total[s], {i, Infinity}]; s = {0}~Join~Map[Which[Length@ # == 0, 0, And[Length@ # == 1, First@ # == 2], 1, True, If[Union@ # == {1}, Length@ # + 1, -1] &[Differences@ PrimePi@ #, {} -> {2}]] &, a]; Array[-1 + Position[s, #][[All, 1]] /. k_ /; MissingQ@ k -> {-1} &, Max@ s + 1, 0]]
%Y A333337 Cf. A330507, A333238, A333259.
%K A333337 tabf,sign
%O A333337 0,3
%A A333337 _Michael De Vlieger_, _David James Sycamore_, May 25 2020