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A269564 Seven-digit primes whose first, third, fifth, and seventh digits are the same. 2
1010131, 1011191, 1012171, 1014121, 1014131, 1014161, 1015171, 1016111, 1017131, 1110181, 1111151, 1111181, 1112131, 1112141, 1112171, 1113181, 1114111, 1115131, 1117111, 1118101, 1119121, 1210151, 1211141, 1211191, 1212121, 1212191, 1213141, 1213151 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are 598 such primes.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..598

EXAMPLE

7671737 is a prime and its first, third, fifth, and seventh digits are the same.

MATHEMATICA

Table[Select[Prime[Range[PrimePi[i*10^6]+1, PrimePi[i*10^6+ 10^6-1]]], MatchQ[ IntegerDigits[#], {x_, _, x_, _, x_, _, x_}]&], {i, {1, 3, 7, 9}}] //Flatten

CROSSREFS

Cf. A269066.

Sequence in context: A306515 A306517 A043643 * A096931 A210274 A252916

Adjacent sequences:  A269561 A269562 A269563 * A269565 A269566 A269567

KEYWORD

nonn,base,fini,full

AUTHOR

Harvey P. Dale, Feb 29 2016

STATUS

approved

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Last modified April 9 06:50 EDT 2020. Contains 333344 sequences. (Running on oeis4.)