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A304242
Increasingly larger (in absolute value) extrema of the Mertens function A002321 between subsequent zeros.
4
1, -4, -6, -8, -9, -12, -15, -16, -25, -29, 35, -43, 51, -72, 73, -88, 96, -113, -132, -134, -154, 240, -258, -278, -368, 432, 550, -683, -847, 1060, -1078, 1240, -1447, -2573, 2845, -3448, -4610, -6226, 6695, -8565, 9132, 10246, -15335, -17334, 21777, -25071
OFFSET
1,2
COMMENTS
Values of A002321 at the indices listed in A304241.
These are those records of the absolute value of A002321 which are the maxima or minima between subsequent zeros. Figuratively speaking, these are the increasingly larger heights of the mountains or depths of the valleys of the graph of A002321.
FORMULA
a(n) = A002321(A304241(n)).
PROG
(PARI) L=M=0; for(n=1, oo, if(m=merten(n), abs(m)>abs(M) && [M, N]=[m, n], abs(M)>abs(L) && (L=M) && print1(L", "); M=0))
(PARI) print1(j=1); for(i=1, #A051402-1, while( A028442[j] < A051402[i], j++); if( A028442[j-(j>1)]<=A051402[i] && A028442[j] < A051402[i+1], print1(", "A002321(A051402[i])))) \\ Using precomputed vectors A002321 and A051402, e.g. from the b-files: {c=0; AX=apply(t->fromdigits(digits(t)[#Str(c++)+1..-1]), readvec("/tmp/bX.txt"))}
CROSSREFS
Cf. A002321, A028442 (zeros of M), A051400, A051401, A051402 (where M, -M, |M| reaches k = 1, 2, 3, ...).
Sequence in context: A258614 A269131 A130074 * A067012 A157942 A122786
KEYWORD
sign,hard
AUTHOR
M. F. Hasler, May 08 2018
EXTENSIONS
More terms from Bert Dobbelaere, Oct 30 2018
STATUS
approved