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A317716
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Square array A(n, k), read by antidiagonals downwards: k-th prime p such that cyclic digit shifts produce exactly n different primes.
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10
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2, 3, 13, 5, 17, 113, 7, 31, 131, 1193, 11, 37, 197, 1931, 11939, 19, 71, 199, 3119, 19391, 193939, 23, 73, 311, 3779, 19937, 199933, 17773937, 29, 79, 337, 7793, 37199, 319993, 39371777, 119139133, 41, 97, 373, 7937, 39119, 331999, 71777393, 133119139
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OFFSET
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1,1
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COMMENTS
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k-th prime p such that A262988(p) = n.
Are all rows of the array infinite?
Row 1 is a supersequence of A004022.
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LINKS
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EXAMPLE
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Array starts
2, 3, 5, 7, 11, 19, 23, ...
13, 17, 31, 37, 71, 73, 79, ...
113, 131, 197, 199, 311, 337, 373, ...
1193, 1931, 3119, 3779, 7793, 7937, 9311, ...
11939, 19391, 19937, 37199, 39119, 71993, 91193, ...
193939, 199933, 319993, 331999, 391939, 393919, 919393, ...
17773937, 39371777, 71777393, 73937177, 77393717, 77739371, 93717773, ...
119139133, 133119139, 139133119, 191391331, 311913913, 331191391, 913311913, ...
...
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PROG
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(PARI) eva(n) = subst(Pol(n), x, 10)
rot(n) = if(#Str(n)==1, v=vector(1), v=vector(#n-1)); for(i=2, #n, v[i-1]=n[i]); u=vector(#n); for(i=1, #n, u[i]=n[i]); v=concat(v, u[1]); v
count_primes(n) = my(d=digits(n), i=0); while(1, if(ispseudoprime(eva(d)), i++); d=rot(d); if(d==digits(n), return(i)))
row(n, terms) = my(i=0); forprime(p=1, , if(count_primes(p)==n, print1(p, ", "); i++); if(i==terms, print(""); break))
array(rows, cols) = for(x=1, rows, row(x, cols))
array(7, 7) \\ print initial 7 rows and 7 columns of array
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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