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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
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 March 29 04:59 EDT 2024. Contains 371264 sequences. (Running on oeis4.)