A166701 Totally multiplicative sequence with a(p) = a(p-1) + 4 for prime p.

1, 5, 9, 25, 29, 45, 49, 125, 81, 145, 149, 225, 229, 245, 261, 625, 629, 405, 409, 725, 441, 745, 749, 1125, 841, 1145, 729, 1225, 1229, 1305, 1309, 3125, 1341, 3145, 1421, 2025, 2029, 2045, 2061, 3625, 3629, 2205, 2209, 3725, 2349, 3745, 3749, 5625, 2401

Offset

1,2

Links

Andrew Howroyd, Table of n, a(n) for n = 1..10000

Formula

Multiplicative with a(p^e) = (a(p-1)+4)^e. If n = Product p(k)^e(k) then a(n) = Product (a(p(k)-1)+4)^e(k).

Prog

(PARI) lista(n)={my(a=vector(n)); for(n=1, n, my(f=factor(n)); a[n] = prod(i=1, #f~, my([p, e]=f[i, ]); (a[p-1] + 4)^e)); a} \\ Andrew Howroyd, Nov 15 2025

Crossrefs

Cf. A166699.

Sequence in context: A162907 A165345 A074741 * A177240 A116520 A273561

Adjacent sequences: A166698 A166699 A166700 * A166702 A166703 A166704

Keyword

nonn,mult

Author

Jaroslav Krizek, Oct 18 2009

Status

approved