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A358677
Irregular triangle where row n gives the columns of A340316 whose minimum value is in row n of A340316. The lists of column indices are given in abbreviated form, using pairs (x, y) to mean the range [x..y].
2
1, 16, 18, 18, 21, 21, 17, 17, 19, 20, 22, 265549, 265604, 265605, 265608, 265681, 265683, 265829, 265831, 265831, 265835, 265836, 265850, 265850, 265853, 265853, 265862, 265873, 265550, 265603, 265606, 265607, 265682, 265682, 265830, 265830, 265832, 265834, 265837, 265849, 265851, 265852, 265854, 265861
OFFSET
1,2
COMMENTS
This sequence is a spin-off from old comments of A340316 (see history there).
Pending availability of tighter constraints, we assume that there are no more values in row n here only after we reach a column of A340316 where the value in A340316 row n is greater than the value in A340316 row n+2.
Presumably, using the results from Landau as they apply to A276176, it can similarly be shown that every row here is finite. - Peter Munn, Dec 20 2022
EXAMPLE
First 2 rows are:
{1..16, 18..18, 21..21} for [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,18,21];
{17..17, 19..20, 22..265549, 265604..265605, 265608..265681, 265683..265829, 265831..265831, 265835..265836, 265850..265850, 265853..265853, 265862..265873}.
The A340316 first 2 rows being:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
-----------------------------------------------------------------
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79
6 10 14 15 21 22 26 33 34 35 38 39 46 51 55 57 58 62 65 69 74 77
the first columns that give row 2: ^^ ^^ ^^ ^^
Row 3 begins: {265550..265603, 265606..265607, 265682..265682, 265830..265830, 265832..265834, ...
PROG
(PARI)
showlist(list) = {my(slist = List()); listput(slist, list[1]); for (i=2, #list, if (list[i] != list[i-1]+1, listput(slist, list[i-1]); listput(slist, list[i]); ); ); listput(slist, list[#list]); Vec(slist); }
primo(i) = factorback(primes(i));
ubound(nL, n) = {if (nL == 1, return(n*log(n) + n*log(log(n)))); if (nL == 2, return(n*log(n)/log(log(n)))); if (nL == 3, return(2*n*log(n)/log(log(n))^2)); if (nL == 4, return(3*n*log(n)/log(log(n))^3)); if (nL == 5, return(4*n*log(n)/log(log(n))^4)); }
out(list1, list2, list3) = print(showlist(list1)); print(showlist(list2)); print(showlist(list3));
rows() = {my(nL = 3, nC = 1000000, nB=5); my(m=vector(nL, i, vector(nC))); my(vfirst = vector(nL, i, primo(i))); my(list1 = List(), list2 = List(), list3 = List()); for (nn=1, nB, my(ok=1); print("nn=", nn); for (i=1, nL, my(list = List()); my(na = vfirst[i]); my(ns = 1); if (nn==1, m[i][ns] = na; ns++); forsquarefree (k=na+1, 100*round(ubound(i, nn*nC)), if (omega(k[2]) == i, m[i][ns] = k[1]; ns++); if (ns > nC, break)); if (ns < nC, print("not enough"); out(list1, list2, list3); return; ); ); N = 1; for (j=1, nC, if (m[N][j] == vecmin (vector(nL, r, m[r][j])), listput(list1, j+(nn-1)*nC)); ); N = 2; for (j=1, nC, if (m[N][j] == vecmin (vector(nL, r, m[r][j])), listput(list2, j+(nn-1)*nC)); ); N = 3; for (j=1, nC, if (m[N][j] == vecmin (vector(nL, r, m[r][j])), listput(list3, j+(nn-1)*nC)); ); vfirst = vector(nL, i, m[i][nC]); for (i=1, nL, m[i] = vector(nC)); ); out(list1, list2, list3); }
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Michel Marcus, Dec 12 2022
EXTENSIONS
Provisional rule for calculating that row n is full added by Peter Munn, Jan 03 2023
STATUS
approved