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A166572 Prime numbers containing the string 11. 5
11, 113, 211, 311, 811, 911, 1103, 1109, 1117, 1123, 1129, 1151, 1153, 1163, 1171, 1181, 1187, 1193, 1511, 1811, 2011, 2111, 2113, 2311, 2411, 2711, 3011, 3119, 3511, 3911, 4111, 4211, 5011, 5113, 5119, 5711, 6011, 6113, 6211, 6311, 6911, 7211, 7411 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

FORMULA

a(n) ~ n log n. - Charles R Greathouse IV, Jun 20 2014

MAPLE

isA166572 := proc(n) local dgs, wrks; if isprime(n) then dgs := convert(n, base, 10) ; wrks := false; for i from 1 to nops(dgs)-1 do if op(i, dgs) = 1 and op(i+1, dgs) = 1 then return true; end if; od: return false; else false; end if; end proc: for n from 1 to 8000 do if isA166572(n) then printf("%d, ", n) ; end if; od: # R. J. Mathar, Nov 30 2009

MATHEMATICA

p11Q[n_]: = Module[{idn = IntegerDigits[n]}, MemberQ[Partition[idn, 2, 1], {1, 1}]] Select[Prime[Range[1000]], p11Q] (* Vincenzo Librandi, Sep 14 2012 *)

PROG

(PARI) contains(n, k)=my(N=digits(n), K=digits(k)); for(i=0, #N-#K, for(j=1, #K, if(N[i+j]!=K[j], next(2))); return(1)); 0

is(n)=isprime(n) && contains(n, 11) \\ Charles R Greathouse IV, Jun 20 2014

CROSSREFS

Cf. A166571, A166573, A166579, A166580, A166581, A166582.

Sequence in context: A175684 A090227 A050758 * A111463 A142483 A001268

Adjacent sequences:  A166569 A166570 A166571 * A166573 A166574 A166575

KEYWORD

nonn,base

AUTHOR

Vincenzo Librandi, Nov 01 2009

STATUS

approved

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Last modified September 22 11:06 EDT 2020. Contains 337289 sequences. (Running on oeis4.)