The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A254341 Lexicographically earliest sequence of distinct numbers with alternating parity such that no sum of consecutive terms is prime. 5
 0, 1, 8, 25, 24, 27, 6, 9, 30, 15, 42, 39, 18, 21, 36, 33, 60, 35, 16, 69, 48, 63, 12, 51, 66, 45, 72, 87, 54, 93, 78, 81, 90, 57, 84, 75, 114, 111, 96, 99, 120, 105, 102, 117, 144, 123, 108, 129, 126, 135, 138, 147, 150, 141, 162, 153, 156, 159, 132, 171, 174, 165, 168, 177, 192, 183, 180, 189, 186, 195, 198, 207, 204, 201, 216, 213, 228, 219, 210, 231, 222, 249, 240, 237, 252, 243, 258, 255, 234, 261, 246, 225, 288, 267, 264, 273, 276, 279, 270 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS In other words, no sum a(i)+a(i+1)+a(i+2)+...+a(j) may be prime. In particular, the sequence may not contain any primes. Without the condition that the parity alternates, it seems that the sequence (A254337) contains only a single odd number. It appears that a(n) ~ 3n. Is there a simple explanation for this? LINKS M. F. Hasler, Table of n, a(n) for n = 0..9999 PROG (PARI) {N=10^3; a=[]; u=0; for(i=0, N, a=concat(a, i%2); until( ! isprime(s) || ! a[#a]+=2, while( isprime(a[#a]) || bittest(u, a[#a]), a[#a]+=2); s=a[k=#a]; while( k>1 && ! isprime( s+=a[k--]), )); u+=2^a[#a])} CROSSREFS Cf. A254337, A153136. Sequence in context: A200838 A302160 A122984 * A188477 A302632 A045860 Adjacent sequences: A254338 A254339 A254340 * A254342 A254343 A254344 KEYWORD nonn AUTHOR M. F. Hasler, Jan 29 2015 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified June 13 05:35 EDT 2024. Contains 373366 sequences. (Running on oeis4.)