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A102141
Iccanobirt prime indices (11 of 15): Indices of prime numbers in A102121.
1
4, 6, 7, 15, 25, 51, 126, 171, 311, 358, 865, 1850, 3311, 4686, 7893, 8249, 17795, 27176, 48728
OFFSET
1,1
COMMENTS
No more terms through 5000.
a(20) > 50000. - Robert Price, Nov 10 2018
FORMULA
A102121(a(n)) = A102161(n).
MATHEMATICA
a[n_] := a[n] =
IntegerReverse[a[n - 1] + IntegerReverse[a[n - 2]] + IntegerReverse[a[n - 3]]];
a[0] = 0; a[1] = 0; a[2] = 1;
Select[Range[0, 5000], PrimeQ[a[#]] &] (* Robert Price, Apr 10 2020 *)
CROSSREFS
KEYWORD
nonn,more,base
AUTHOR
EXTENSIONS
a(15)-a(19) from Robert Price, Nov 10 2018
STATUS
approved