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A133211
Sum of all n-digit Perrin numbers.
0
27, 338, 3113, 29524, 280003, 3619458, 33362676, 316408590, 3000790339, 28459223116, 367878072268, 3390948851403, 32159451022886, 304997313558856, 2892566829325533, 37390757461695633, 344652632558806213, 3268654274185743387, 30999620356388134160, 293997584825511430878
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Perrin Sequence.
EXAMPLE
Sum of all 1-digit Perrin numbers = 3 + 0 + 2 + 3 + 2 + 5 + 5 + 7 = 27.
Sum of all 2-digit Perrin numbers = 10 + 12 + 17 + 22 + 29 + 39 + 51 + 68 + 90 = 338.
Sum of all 3-digit Perrin numbers = 119 + 158 + 209 + 277 + 367 + 486 + 644 + 853 = 3113.
MATHEMATICA
a[n_] := a[n] = a[n - 2] + a[n - 3]; a[0] = 3; a[1] = 0; a[2] = 2; t = Table[a@n, {n, 0, 150}]; Table[Plus @@ Select[t, 10^(n - 1) -1 < # < 10^n &], {n, 18}] - Robert G. Wilson v, Oct 14 2007
With[{pernos=LinearRecurrence[{0, 1, 1}, {3, 0, 2}, 200]}, Table[Total[ Select[ pernos, IntegerLength[#]==n&]], {n, 20}]] (* Harvey P. Dale, Apr 20 2012 *)
CROSSREFS
Cf. A001608.
Sequence in context: A160223 A182668 A076394 * A178983 A029947 A030673
KEYWORD
nonn,base,less
AUTHOR
Parthasarathy Nambi, Oct 11 2007
EXTENSIONS
More terms from Robert G. Wilson v, Oct 14 2007
More terms from Amiram Eldar, Nov 30 2019
STATUS
approved