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A077652
Primes whose initial and terminal decimal digits are identical.
3
2, 3, 5, 7, 11, 101, 131, 151, 181, 191, 313, 353, 373, 383, 727, 757, 787, 797, 919, 929, 1021, 1031, 1051, 1061, 1091, 1151, 1171, 1181, 1201, 1231, 1291, 1301, 1321, 1361, 1381, 1451, 1471, 1481, 1511, 1531, 1571, 1601, 1621, 1721, 1741, 1801, 1811
OFFSET
1,1
COMMENTS
1021 is the smallest of these not to be palindromic. - Jonathan Vos Post, Nov 02 2013
All palindromic primes (A002385) except 11 have an odd number of digits, therefore all terms > 11 with an even number of digits are non-palindromic in this sequence. - M. F. Hasler, Nov 02 2013
LINKS
MATHEMATICA
Do[s1=First[IntegerDigits[Prime[n]]]; s2=Last[IntegerDigits[Prime[n]]]; If[Equal[s1, s2], Print[Prime[n]]], {n, 1, 1000}]
itdQ[n_]:=Module[{idn=IntegerDigits[n]}, idn[[1]]==idn[[-1]]]; Select[Prime[ Range[ 500]], itdQ] (* Harvey P. Dale, Apr 12 2013 *)
PROG
(Magma) [ p: p in PrimesUpTo(2000) | P[#P] eq P[1] where P is Intseq(p) ]; // Bruno Berselli, Jul 26 2011
(PARI) is(n)=digits(n)[1]==n%10&&isprime(n) \\ M. F. Hasler, Nov 02 2013
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Nov 19 2002
STATUS
approved