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A261173
Table read by antidiagonals: T(n,k) = smallest prime p containing only digits 0 and 1 with n 0's and k 1's, or 0 if no such p exists.
1
11, 0, 101, 0, 0, 0, 0, 10111, 0, 0, 0, 101111, 0, 0, 0, 0, 0, 0, 1011001, 0, 0, 0, 11110111, 0, 10011101, 10010101, 0, 0, 0, 101111111, 101101111, 0, 100100111, 101001001, 0, 0, 0, 0, 1010111111, 1001110111, 0, 1000011011, 1000001011, 0, 0
OFFSET
0,1
COMMENTS
T(n, k) = 0 if k is a term of A008585.
T(0, k) != 0 iff k is a term of A004023.
T(1, k) = A157709(k-2) for all k >= 4.
T(n, 2) != 0 iff A062397(n+1) is prime.
a(n) is in A168586 iff it is the smallest p in T with A007953(p) = k.
LINKS
EXAMPLE
Table T(n, k) starts
k = 2 3 4 5
-------------------------------------
n = 0 | 11 0 0 0
n = 1 | 101 0 10111 101111
n = 2 | 0 0 0 0
n = 3 | 0 0 1011001 10011101
PROG
(PARI) a(n, k) = i=0; forprime(p=10^(n+k-1), (10^(n+k)-1)/9, if(vecmax(digits(p))==1 && sumdigits(p)==k, return(p); i++; break)); if(i==0, return(0))
table(row, col) = for(x=0, row, for(y=2, col, print1(a(x, y), " ")); print(""))
table(4, 5) \\ print 5 X 4 table
CROSSREFS
Sequence in context: A185682 A217752 A335646 * A287468 A110417 A240560
KEYWORD
nonn,tabl,base
AUTHOR
Felix Fröhlich, Aug 10 2015
EXTENSIONS
More terms from Alois P. Heinz, Aug 17 2015
STATUS
approved