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A317919 Number of Wieferich tuples with A297846(n) as largest member, i.e., number of rows of the array in A317721 where A297846(n) is the largest element of that row. 3
1, 3, 2, 7, 1, 2, 1, 6, 1, 317, 1, 1, 230, 580 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

For n = 2: The second prime that occurs in column 1 of the array in A317721 is 359. 359 occurs as the largest element in 3 rows of the array, so a(2) = 3.

PROG

(PARI) addtovec(vec) = my(w=[], vmax=0); for(t=1, #vec, if(vecmax(vec[t]) > vmax, vmax=vecmax(vec[t]))); for(k=1, #vec, forprime(q=1, vmax, if(Mod(vec[k][#vec[k]], q^2)^(q-1)==1, w=concat(w, [0]); w[#w]=concat(vec[k], [q])))); w

removefromvec(vec) = my(w=[]); for(k=1, #vec, if(vecsort(vec[k])==vecsort(vec[k], , 8), w=concat(w, [0]); w[#w]=vec[k])); w

forprime(p=1, , my(v=[[p]], i=0); while(#v > 0, v=addtovec(v); for(k=1, #v, if(v[k][1]==v[k][#v[k]], i++)); v=removefromvec(v)); if(i > 0, print1(i, ", ")))

CROSSREFS

Cf. A297846, A317721, A317920.

Sequence in context: A019971 A330501 A010606 * A255820 A318436 A243375

Adjacent sequences:  A317916 A317917 A317918 * A317920 A317921 A317922

KEYWORD

nonn,more

AUTHOR

Felix Fröhlich, Aug 21 2018

STATUS

approved

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Last modified September 19 17:46 EDT 2021. Contains 347564 sequences. (Running on oeis4.)