A246351 - OEIS

A246351

Numbers n such that A048673(n) < n.

5, 7, 11, 13, 17, 19, 22, 23, 29, 31, 34, 37, 38, 41, 43, 46, 47, 51, 53, 55, 58, 59, 61, 62, 65, 67, 71, 73, 74, 77, 79, 82, 83, 85, 86, 87, 89, 94, 95, 97, 101, 103, 106, 107, 109, 111, 113, 115, 118, 119, 121, 122, 123, 127, 129, 131, 133, 134, 137, 139, 141, 142, 143, 145, 146, 149, 151, 155, 157, 158, 159

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

The growth rate of the sequence seems to converge:

a(100) = 217

a(1000) = 2231

a(10000) = 21535

a(100000) = 214647

a(1000000) = 2155903

a(10000000) = 21553153

Please see comments in A246282.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

PROG

(PARI)

default(primelimit, 2^22);

A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From Michel Marcus

A048673(n) = (A003961(n)+1)/2;

isA246351(n) = (A048673(n) < n);

n = 0; i = 0; while(i < 10000, n++; if(isA246351(n), i++; write("b246351.txt", i, " ", n)));

(Scheme, with Antti Karttunen's IntSeq-library)

(define A246351 (MATCHING-POS 1 1 (lambda (n) (< (A048673 n) n))))

CROSSREFS

Complement: A246352.

Setwise difference of A246281 and A048674.

Cf. A048673, A246371, A246282.

Sequence in context: A348471 A101550 A320048 * A272260 A322271 A306289

Adjacent sequences: A246348 A246349 A246350 * A246352 A246353 A246354

KEYWORD

nonn

AUTHOR

Antti Karttunen, Aug 24 2014

STATUS

approved