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 A111463 a(1) = 11, then least prime beginning with the digit reversal of the previous term. 2
 11, 113, 311, 11311, 113111, 11131111, 11113111, 1113111107, 7011113111, 111311110717, 717011113111, 111311110717, 71701111311131, 1311131111071703, 307170111131113123, 32131113111107170309, 9030717011113111312321 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(3) = 311 because the reversal of a(2) = 113 is 311 and 311 is prime. a(4) = 11311 because the reversal of a(3) = 311 is 113, which is already in the list. The next smallest prime that starts with 113 is 11311. MAPLE reverse := proc (nn) local n, m; m := 0; n := nn; while (n > 0) do m := m*10 + irem(n, 10, 'n'); od; m; end: a := proc(n, m) option remember; global currSet; local currN, i, origN, j; if n = 0 then currSet := {m}; return m; end if; currN := reverse(a(n - 1, m)); if (not (evalb(currN in currSet))) then if (isprime(currN)) then currSet := currSet union {currN}; return currN; end if; end if; origN := currN; j := 1; while (true) do origN := 10 * origN; currN := origN; i := 0; while i < (10^j) do if (isprime(currN) and (not evalb(currN in currSet))) then currSet := currSet union {currN}; return currN; end if; currN := currN + 1; i := i + 1; end do; j := j + 1; end do; return currN; end proc; (Deugau) CROSSREFS Cf. A090543, A111462. Sequence in context: A090227 A050758 A166572 * A142483 A001268 A065538 Adjacent sequences:  A111460 A111461 A111462 * A111464 A111465 A111466 KEYWORD base,nonn AUTHOR Amarnath Murthy, Aug 04 2005 EXTENSIONS More terms from Chris Deugau (deugaucj(AT)uvic.ca), Nov 04 2005 STATUS approved

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Last modified September 18 16:56 EDT 2021. Contains 347532 sequences. (Running on oeis4.)