A036344 Prime concatenated analog clock numbers (clockwise and counterclockwise).

2, 3, 5, 7, 11, 23, 43, 67, 89, 109, 4567, 10987, 76543, 23456789, 6543211211, 4321121110987, 23456789101112123, 891011121234567891011, 3211211109876543211211, 23456789101112123456789101112123, 43211211109876543211211109876543, 567891011121234567891011121234567891011

Offset

1,1

Comments

The hours 10, 11 and 12 are taken 'complete and unreversed'.

Links

Michael S. Branicky, Table of n, a(n) for n = 1..40

Carlos Rivera, Puzzle 19. Primes on a clock, The Prime Puzzles & Problems Connection.

Eric Weisstein's World of Mathematics, Clock Prime.

Formula

Union of A036342 and A036343. - Sean A. Irvine, Oct 26 2020

Crossrefs

Cf. A034326, A036342, A036343.

Sequence in context: A030284 A252791 A068148 * A165802 A107798 A119660

Adjacent sequences: A036341 A036342 A036343 * A036345 A036346 A036347

Keyword

nonn,base

Author

Patrick De Geest, Dec 15 1998

Extensions

Offset corrected and a(21) from Sean A. Irvine, Oct 26 2020

a(22) and beyond from Michael S. Branicky, May 20 2024

Status

approved