A215525 a(0)=a(1)=1, a(n) = a(n-1) + a(a(n-2) mod n).

1, 1, 2, 3, 5, 8, 16, 17, 18, 36, 54, 57, 73, 81, 84, 100, 105, 205, 305, 405, 413, 429, 634, 734, 788, 824, 842, 926, 928, 1854, 2782, 3606, 6388, 6424, 9206, 9611, 10453, 11381, 11384, 17772, 18560, 18965, 30349, 30351, 36775, 37204, 37633, 38559, 38560, 75764

Offset

0,3

Comments

Same formula, seed {0,1} : 0, 1, 1, 2, 3, 4, 6, 9, 15, 15, 19, 22, 31, 46, 48, 49, 49, 98, 144, 146, 149, 298, 396, 792, 823, 921, 1019, 1021, 1043, 1049, 1841, 2860

Same formula, seed {1,2} : 1, 2, 4, 8, 9, 17, 25, 33, 35, 60, 77, 94, 111, 119, 238, 476, 714, 715, 826, 937, 962, 1081, 1795, 1796, 2733, 3814, 3822, 3855, 4093, 7948

Links

Ivan Neretin, Table of n, a(n) for n = 0..10000

Formula

a(0)=a(1)=1, for n>=2, a(n) = a(n-1) + a(a(n-2) mod n).

Mathematica

Fold[Append[#1, #1[[-1]] + #1[[1 + Mod[#1[[-2]], #2]]]] &, {1, 1}, Range[2, 49]] (* Ivan Neretin, Sep 07 2017 *)

Prog

(Python)
a = [1]*1000
for n in range(2, 77):
..print(a[n-2], end=', ')
..a[n] = a[n-1] + a[a[n-2] % n]
# Corrected by Derek Orr, Sep 25 2014

Crossrefs

Cf. A215488.

Sequence in context: A096592 A305370 A192571 * A192645 A050295 A121649

Adjacent sequences: A215522 A215523 A215524 * A215526 A215527 A215528

Keyword

nonn,easy

Author

Alex Ratushnyak, Aug 14 2012

Status

approved