A249339 Positions of ones in A249336; positions of zeros in A249338.

1, 2, 4, 6, 14, 21, 40, 51, 71, 81, 98, 132, 143, 194, 241, 258, 297, 323, 380, 398, 436, 479, 491, 543, 570, 630, 737, 759, 765, 829, 836, 873, 1068, 1101, 1210, 1215, 1370, 1415, 1469, 1515, 1550, 1607, 1682, 1701, 1854, 1872, 1904, 1932, 2117, 2245, 2294, 2304, 2344

Offset

1,2

Links

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

Formula

For n >= 2, a(n) = 1 + A249340(n-1).

Prog

(PARI)
allocatemem(234567890);
A049084(n) = if(isprime(n), primepi(n), 0); \\ This function from Charles R Greathouse IV
A056239(n) = { my(f); if(1==n, 0, f=factor(n); sum(i=1, #f~, f[i, 2] * A049084(f[i, 1]))); }
A249339_write_bfile(up_to_n) = { my(counts, n, k, a_k); counts = vector(min((2^24)-8, up_to_n^2)); n = 0; k = 0; a_k = 1; while(n < up_to_n, k++; if((0 == A056239(a_k)), n++; write("b249339.txt", n, " ", k)); counts[1+A056239(a_k)]++; a_k = counts[1+A056239(a_k)]); };
A249339_write_bfile(10000);
(Scheme, with Antti Karttunen's IntSeq-library, two alternative definitions)
(define A249339 (MATCHING-POS 1 1 (lambda (n) (= 1 (A249336 n)))))
(define A249339 (ZERO-POS 1 1 A249338))

Crossrefs

Cf. A249336, A249338, A249340, A249341.

Sequence in context: A226302 A337499 A284886 * A332754 A307676 A084685

Adjacent sequences: A249336 A249337 A249338 * A249340 A249341 A249342

Keyword

nonn

Author

Antti Karttunen, Oct 26 2014

Status

approved