A349937 Odd numbers k > 1 such that A309906(k-1) < A309906(k) > A309906(k+1).

315, 525, 693, 765, 825, 945, 1125, 1155, 1323, 1395, 1575, 1683, 1725, 1755, 1785, 1815, 1845, 1995, 2205, 2275, 2277, 2415, 2457, 2475, 2535, 2565, 2691, 2695, 2793, 2805, 2835, 2907, 3003, 3045, 3285, 3315, 3375, 3465, 3591, 3645, 3675, 3705, 3735, 3825, 3885

Offset

1,1

Comments

Conjecturally, odd numbers k > 1 such that liminf_{n->oo} d(p(n)^(k-1)-1) < liminf_{n->oo} d(p(n)^k-1) > liminf_{n->oo} d(p(n)^(k+1)-1), where p(n) = prime(n), d = A000005.

If k is odd, then A079612(k) = 2, so A309906(k) is usually smaller than either A309906(k-1) or A309906(k+1) (or both). This sequence lists the exceptions.

Links

Table of n, a(n) for n=1..45.

Example

A309906(314) = 128 < A309906(315) = 8192 > A309906(316) = 2560, so 315 is a term.

Prog

(PARI) isA349937(k) = (k%2&&k>1) && A309906(k)>A309906(k-1) && A309906(k)>A309906(k+1) \\ See A309906 for its program

Crossrefs

Cf. A309906, A349938, A349941.

Sequence in context: A256575 A295990 A349868 * A076773 A114807 A109130

Adjacent sequences: A349934 A349935 A349936 * A349938 A349939 A349940

Keyword

nonn

Author

Jianing Song, Dec 05 2021

Status

approved