A353568 Prime shadows of (nonzero) K-champion numbers.

1, 3, 4, 5, 6, 10, 9, 14, 15, 22, 20, 21, 26, 28, 33, 30, 35, 44, 39, 42, 55, 52, 51, 66, 65, 68, 70, 57, 78, 85, 110, 102, 95, 130, 114, 170, 138, 182, 220, 190, 174, 238, 260, 230, 255, 266, 340, 290, 276, 285, 322, 380, 310, 418, 345, 476, 406, 460, 370, 510, 506, 435, 532, 434, 580, 483, 570, 638, 465, 644, 518

Offset

1,2

Comments

Sequence is injective (no duplicate values occur) because A307866 (after its initial zero) is a subsequence of A025487.

The finite number of powerful (A001694) terms in A307866 implies a finite number of odd terms in this sequence.

Links

Amiram Eldar, Table of n, a(n) for n = 1..883

Formula

a(n) = A181819(A307866(1+n)).

a(n) = A122111(A330686(n)).

Prog

(PARI)
v307866 = readvec("b307866_to.txt"; ) \\ Prepared from the b-file of A307866 with gawk ' { print $2 } ' < b307866.txt > b307866_to.txt
A307866(n) = v307866[n];
A181819(n) = factorback(apply(e->prime(e), (factor(n)[, 2])));
A353568(n) = A181819(A307866(1+n));

Crossrefs

Cf. A025487, A122111, A181819, A307866, A330686.

Cf. also A353561, A353562.

Sequence in context: A039035 A065798 A082671 * A364146 A059877 A047307

Adjacent sequences: A353565 A353566 A353567 * A353569 A353570 A353571

Keyword

nonn

Author

Antti Karttunen, Apr 29 2022

Status

approved