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A281256 Runs of consecutive integers in A270877, which is produced by a decaying trapezoidal modification of the sieve of Eratosthenes.

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%I A281256 #11 Jan 20 2017 19:58:18
%S A281256 8,13,1,19,16,4,32,64,22,49,34,166,27,71,38,44,172,59,302,1984,46771,
%T A281256 56,178,94,346,4925,59492,188357,68,205,352,617,7408,113492,371918,
%U A281256 881212,80,211,382,939,9110,114602,964583,6671161,24365591,89,214,581,1011,11090,207938,1008362
%N A281256 Runs of consecutive integers in A270877, which is produced by a decaying trapezoidal modification of the sieve of Eratosthenes.
%C A281256 Square table T, read by ascending antidiagonals, where T(n,m) gives the least integer in the n-th occurrence of a run of exactly m consecutive integers in the ordered sequence A270877.
%C A281256 A270877 is sifted from the positive integers by modifying the sieve of Eratosthenes: instead of eliminating integers that would enumerate a rectangular area dot pattern with one side held at a constant length (equal to each surviving integer in turn), the sieve eliminates those enumerating a trapezoidal area dot pattern with the constant length being the trapezoid's longest side. Given this geometric relationship, it is considered worth looking for qualities that A270877 may have in common with the sequence of primes, potentially influenced by related causes such as the effect of prime factors on A270877.
%C A281256 The columns of this sequence, listing the runs of m consecutive integers within A270877, merit comparative examination with equivalent sequences for prime k-tuples. For m=5, the notably larger ratio between T(1,5) and T(2,5) resembles early large ratio gaps in the occurrence sequences of k-tuples such as A022008 (sextuples), whereas columns m<5 are more comparable with those for shorter k-tuples such as A001359 (twin primes) and A007530 (quadruples), each having a relatively low-valued first term (less than 60) and without such a large ratio gap. In comparison, the columns for runs m>5 appear more like the sequences for some longer k-tuples such as A027570 (a 10-tuple sequence). Row 1 merits comparative examination with A186702 for primes.
%C A281256 The author conjectures that T(n,m) exists for all n>=1, m>=1.
%e A281256 4, 5 and 6 occur in A270877, but 3 and 7 do not. This is the first run of exactly 3 consecutive integers in A270877, so T(1,3) = 4.
%e A281256 Square table T(n,m) begins:
%e A281256    8,   1,   4,   49,    38,  46771,  188357,   881212, ...
%e A281256   13,  16,  22,   71,  1984,  59492,  371918,  6671161, ...
%e A281256   19,  64,  27,  302,  4925, 113492,  964583,  8799769, ...
%e A281256   32, 166,  59,  346,  7408, 114602, 1008362, 13579777, ...
%e A281256   34, 172,  94,  617,  9110, 207938, 1094293, 14874616, ...
%e A281256   44, 178, 352,  939, 11090, 291712, 1156214, 15974752, ...
%e A281256   56, 205, 382, 1011, 13007, 323716, 1239046, 20585962, ...
%e A281256   68, 211, 581, 1080, 13216, 429915, 1433918, 20745838, ...
%e A281256   80, 214, 599, 1091, 14710, 442807, 1702694, 24321313, ...
%e A281256   89, 223, 624, 1151, 15052, 457220, 1712927, 25634557, ...
%Y A281256 This is an analysis of A270877.
%Y A281256 Cf. A001359, A007530, A022008, A027570, A186702.
%K A281256 nonn,tabl
%O A281256 1,1
%A A281256 _Peter Munn_, Jan 18 2017