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A084414 Smallest prime > n having "n" as central digits(s). 3
101, 113, 127, 131, 149, 151, 163, 173, 181, 191, 1103, 1117, 1123, 2131, 2141, 1151, 1163, 1171, 1181, 1193, 1201, 1213, 1223, 1231, 1249, 1259, 2267, 1277, 1283, 1291, 1301, 1319, 1321, 2333, 2341, 2351, 1361, 1373, 1381, 1399, 1409, 2411, 1423, 1433, 1447 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

a(n) >= A084413(n), with equality when n is prime. - Michel Marcus, Oct 05 2013

LINKS

Table of n, a(n) for n=0..44.

EXAMPLE

a(1)=113 because 113 is the smallest prime >1 having "1" as central digit.

PROG

(PARI) a(n) = {for (i = 1, 9, forstep (j=1, 9, 2, v = j + 10*n + i*10^(1+length(Str(n))); if (isprime(v), return (v)); ); ); } \\ code assumes only 1 digit on each side of 'n' will be necessary. See A032734 for numbers that need a better script. - Michel Marcus, Oct 05 2013

CROSSREFS

Cf. A030665, A069691, A077501.

Sequence in context: A084413 A248533 A069691 * A164937 A105992 A038370

Adjacent sequences:  A084411 A084412 A084413 * A084415 A084416 A084417

KEYWORD

easy,nonn,base

AUTHOR

Zak Seidov, Jun 24 2003

EXTENSIONS

a(21) inserted and more terms from Michel Marcus, Oct 05 2013

STATUS

approved

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Last modified July 21 06:55 EDT 2019. Contains 325192 sequences. (Running on oeis4.)