A276555 Number of steps to reach 1 when starting from n and iterating the map x -> x - A061395(x).

0, 1, 1, 2, 2, 3, 2, 3, 3, 3, 4, 4, 3, 4, 5, 6, 4, 7, 5, 5, 5, 5, 5, 6, 6, 6, 7, 7, 6, 8, 6, 7, 8, 8, 7, 9, 7, 9, 9, 8, 8, 10, 7, 10, 11, 8, 8, 9, 12, 9, 11, 9, 8, 10, 10, 10, 13, 10, 11, 14, 8, 12, 12, 13, 12, 9, 10, 9, 15, 10, 12, 11, 10, 13, 12, 10, 12, 12

Offset

1,4

Comments

This sequence tends to infinity as n tends to infinity.

This sequence is similar to A282630; here we consider the greatest prime factor of a number, there we consider its least prime factor.

Links

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, Illustration of the first terms

Rémy Sigrist, Scatterplot of the ordinal transform of the first million terms

Prog

(PARI) a = vector(100); for (n=1, #a, if (n>1, my (f=factor(n)); a[n] = 1 + a[n - primepi(f[#f~, 1])]); print1 (a[n] ", "))

Crossrefs

Cf. A061395, A282630.

Sequence in context: A359728 A217865 A185166 * A348190 A211100 A329326

Adjacent sequences: A276552 A276553 A276554 * A276556 A276557 A276558

Keyword

nonn

Author

Rémy Sigrist, Apr 10 2017

Status

approved