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 A068835 Start of first occurrence of just n consecutive primes with all even digits except the least significant digit. 0
 2, 23, 41, 821, 4409, 2063, 224401, 8609, 20066003, 20628046223, 82260284069, 2248462002229, 224682444608243 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS If the least significant digit must be odd, then a(1) = 241. a(14) > 2*10^15. [From Donovan Johnson, Sep 21 2010] LINKS EXAMPLE a(8) = 8609: the 8 consecutive primes are 8609, 8623, 8627, 8629, 8641, 8647, 8663, 8669. MATHEMATICA a = {0, 1, 1, 1}; Do[ If[ Union[ EvenQ[ Drop[ IntegerDigits[ Prime[n]], -1]]] == {True}, a = Append[a, 1], a = Append[a, 0]], {n, 5, 10^5}]; Do[k = 3; b = Table[1, {n}]; b = Insert[b, 0, {{1}, {-1}}]; While[k < 10^5 - n && Take[a, {k - 1, k + n}] != b, k++ ]; If[k < 10^5, Print[ Prime[k]], Print[0]], {n, 1, 8}] CROSSREFS Sequence in context: A106736 A045392 A107374 * A156557 A002428 A105440 Adjacent sequences:  A068832 A068833 A068834 * A068836 A068837 A068838 KEYWORD more,nonn,base AUTHOR Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 09 2002 EXTENSIONS Edited and extended by Robert G. Wilson v, Apr 10 2002 a(9)-a(12) from Donovan Johnson, Sep 03 2008 a(13) from Donovan Johnson, Sep 21 2010 STATUS approved

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