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 A100763 a(1) = 2; for n>1, a(n) is the least prime with all prime digits which is == 1 (mod a(n-1)). 0
 2, 3, 7, 337, 32353, 7727255227, 23523352753755575323 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(7) > 2*10^19. - Robert G. Wilson v, Nov 27 2004 a(8) > 2*10^32. - Jon E. Schoenfield, Mar 29 2015 LINKS EXAMPLE a(4) = 337, a(5) = 32353 == 1 (mod 337). MATHEMATICA a[1] = 2; a[n_] := a[n] = Block[{k = 1, p = a[n - 1]}, While[ !PrimeQ[k*p + 1] || Union[ Join[{2, 3, 5, 7}, IntegerDigits[k*p + 1]]] != {2, 3, 5, 7}, k++ ]; k*p + 1]; Table[ a[n], {n, 6}] (* Robert G. Wilson v, Nov 27 2004 *) CROSSREFS Sequence in context: A079637 A062662 A084727 * A132538 A334726 A062615 Adjacent sequences:  A100760 A100761 A100762 * A100764 A100765 A100766 KEYWORD base,nonn AUTHOR Amarnath Murthy, Nov 25 2004 EXTENSIONS a(6) from Robert G. Wilson v, Nov 27 2004 a(7) from Jon E. Schoenfield, Mar 29 2015 STATUS approved

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Last modified May 12 10:54 EDT 2021. Contains 343821 sequences. (Running on oeis4.)