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A050678 First occurrence of n in A050677. 1
1, 2, 5, 8, 9, 15, 17, 30, 26, 18 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..10.

P. De Geest, Reversed Smarandache Concatenated Numbers, Prime factors from n down to 1

C. Rivera, Primes by Listing

M. Fleuren, Factors and primes of Smarandache sequences.

M. Fleuren, Smarandache Factors and Reverse factors

MATHEMATICA

Join[{1}, Table[i=1; While[PrimeOmega[FromDigits[Flatten[IntegerDigits[Range[i, 1, -1]]]]]!=n, i++]; i, {n, 2, 10}]] (* Jayanta Basu, May 30 2013 *)

CROSSREFS

Cf. A000422, A050676, A050677.

Sequence in context: A032684 A026448 A258353 * A173286 A243182 A088620

Adjacent sequences:  A050675 A050676 A050677 * A050679 A050680 A050681

KEYWORD

nonn,base,hard

AUTHOR

Patrick De Geest, Aug 15 1999

STATUS

approved

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Last modified October 25 23:17 EDT 2020. Contains 338026 sequences. (Running on oeis4.)