A305235 Smallest positive number k such that there are exactly n successive equal values of A001221 starting at k, i.e., such that A305234(k) = n.

1, 4, 3, 2, 54, 91, 142, 141, 44360, 48919, 218972, 526097, 526096, 526095, 17233173, 127890362, 29138958036, 118968284929, 118968284928, 585927201065, 585927201064, 585927201063, 585927201062, 313978488186061, 453918847597185, 453918847597184, 455626105596320

Offset: 0

Author

Felix Fröhlich, May 28 2018

Keywords

• nonn

Comments

a(27) > 2 * 10^15. - Toshitaka Suzuki, Jun 22 2025

Examples

			For n = 5: A001221(91+k) = 2 for k = 0..5 and 91 is the smallest number x with exactly 5 successors that have the same value of A001221 as x, so a(5) = 91.
		

Crossrefs

Cf. A001221, A001274, A045983, A048932, A048971, A077657, A305234.

Programs

PARI

a305234(n) = my(k=n+1, i=0); while(omega(k)==omega(n), i++; k++); i
a(n) = my(k=1); while(1, if(a305234(k)==n, return(k)); k++)

Extensions

a(16)-a(22) from Toshitaka Suzuki, Apr 01 2025

a(23)-a(26) from Toshitaka Suzuki, Jun 22 2025