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A067860 n is prime and the concatenation of numbers n_1, n_2, n_3, in that order, with n_1 + n_2 = n_3. (Do not allow leading zeros for nonzero n_i.) 0
101, 167, 257, 347, 617, 5813, 7411, 8311, 8513, 9413, 9817, 10111, 10313, 11213, 11617, 12113, 12829, 13417, 13619, 14243, 14519, 14923, 15217, 15823, 15859, 16061, 16319, 17623, 18119, 18523, 19423, 19697, 20323, 20929, 21517, 22123 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..36.

EXAMPLE

167 is the concatenation of 1, 6, 7 and 1+6 = 7.

PROG

(PARI) is(n)=my(d=digits(n)); for(i=1, #d-2, for(j=i+1, #d-1, if(digits(fromdigits(d[1..i])+fromdigits(d[i+1..j]))==d[j+1..#d] && (d[i+1] || i==j+1), return(isprime(n))))); 0

select(is, primes(10^4)) \\ Charles R Greathouse IV, Sep 21 2015

CROSSREFS

Sequence in context: A142660 A123037 A142012 * A140037 A107209 A076613

Adjacent sequences:  A067857 A067858 A067859 * A067861 A067862 A067863

KEYWORD

base,nonn

AUTHOR

Joseph L. Pe, Feb 15 2002

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Jun 11 2002

STATUS

approved

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Last modified July 5 19:02 EDT 2020. Contains 335473 sequences. (Running on oeis4.)