A249341 Positions of ones in A249337; positions of zeros in A249072.

1, 3, 7, 14, 21, 40, 46, 71, 81, 98, 122, 146, 194, 241, 258, 297, 323, 380, 401, 433, 482, 491, 533, 567, 633, 716, 761, 767, 808, 836, 879, 1068, 1105, 1210, 1216, 1370, 1415, 1469, 1515, 1541, 1606, 1684, 1707, 1854, 1872, 1906, 1936, 2117, 2277, 2294, 2305, 2344

Offset

1,2

Links

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

Formula

For all n >= 2: a(n) = A249342(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]))); }
A249341_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((1 == a_k), n++; write("b249341.txt", n, " ", k)); counts[1+A056239(a_k)]++; if(1 == k, a_k = 2, a_k = counts[1+A056239(a_k)])); };
A249341_write_bfile(10000);
(Scheme, with Antti Karttunen's IntSeq-library, two alternative definitions)
(define A249341 (MATCHING-POS 1 1 (lambda (n) (= 1 (A249337 n)))))
(define A249341 (ZERO-POS 1 1 A249072))

Crossrefs

After the initial term, one more than A249342.

Cf. A249337, A249339, A249072.

Sequence in context: A256059 A347349 A258434 * A310278 A154772 A156859

Adjacent sequences: A249338 A249339 A249340 * A249342 A249343 A249344

Keyword

nonn

Author

Antti Karttunen, Oct 26 2014

Status

approved