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A270975 Indices i such that A055773(i) is not equal to A130087(i). 0
4, 5, 897, 898, 899, 900, 901, 902, 903, 904, 905, 906, 907, 908, 909, 910, 911, 912, 913, 914, 915, 916, 917, 918, 919, 920, 921, 922, 923, 924, 925, 926, 927, 928, 929, 930, 931, 932, 933, 934, 935, 936, 937, 938, 939, 940, 941, 942, 1105, 1106, 1107 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A number-theoretic explanation as to 'why' there is such a large gap between a(2) and a(3) is given in the Mathematics Stack Exchange link given below.

LINKS

Table of n, a(n) for n=1..51.

J. M. Campbell et al., A problem involving the product prod_{k=1..n} k^mu(k), where mu denotes the Möbius function, Math. Stack Exchange (2016).

EXAMPLE

A055773(897) is approximately equal to 3.6*10^191 and A130087(897) is approximately equal to 8.4*10^192. The third index i such that A055773(i) is not equal to A130087(i) is i=897, and thus a(3)=897.

PROG

(PARI) A055773(n)=prod(i=primepi(n/2)+1, primepi(n), prime(i));

A130087(n)=denominator(prod(k=1, n, k^moebius(k)));

for(i=0, 2000, if(A055773(i)!=A130087(i), print(i)))

CROSSREFS

Cf. A055773, A130087.

Sequence in context: A134463 A298938 A309071 * A058916 A064612 A299639

Adjacent sequences:  A270972 A270973 A270974 * A270976 A270977 A270978

KEYWORD

nonn

AUTHOR

John M. Campbell, Mar 27 2016

STATUS

approved

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Last modified April 8 09:44 EDT 2020. Contains 333313 sequences. (Running on oeis4.)