A324293 a(n) = A002487(sigma(n)).

1, 2, 1, 3, 2, 2, 1, 4, 5, 4, 2, 3, 3, 2, 2, 5, 4, 10, 3, 8, 1, 4, 2, 4, 5, 8, 3, 3, 4, 4, 1, 6, 2, 8, 2, 19, 7, 4, 3, 12, 8, 2, 5, 8, 10, 4, 2, 5, 10, 16, 4, 9, 8, 4, 4, 4, 3, 12, 4, 8, 5, 2, 5, 7, 8, 4, 5, 6, 2, 4, 4, 20, 11, 10, 5, 9, 2, 8, 3, 16, 13, 6, 8, 3, 8, 6, 4, 12, 12, 18, 3, 8, 1, 4, 4, 6, 9, 34, 10, 27, 12, 8, 5, 18, 2

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..16384

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537

Index entries for sequences related to sigma(n)

Index entries for sequences related to Stern's sequences

Formula

a(n) = A002487(A000203(n)).

Prog

(PARI)
A002487(n) = { my(s=sign(n), a=1, b=0); n = abs(n); while(n>0, if(bitand(n, 1), b+=a, a+=b); n>>=1); (s*b); }; \\ Modified from the one given in A002487, sign not actually needed here.
A324293(n) = A002487(sigma(n));

Crossrefs

Cf. A000203, A002487, A324287, A324294.

Sequence in context: A369467 A227277 A071481 * A336927 A318832 A162348

Adjacent sequences: A324290 A324291 A324292 * A324294 A324295 A324296

Keyword

nonn

Author

Antti Karttunen, Feb 22 2019

Status

approved