A178054 Numbers representing the index of the day of week for the first day of the month in the Gregorian calendar.

6, 2, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5, 1, 4, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6, 2, 5, 5, 1, 3, 6, 1, 4, 0, 2, 5, 0, 3, 6, 6, 2, 4, 0, 2, 5, 1, 3, 6, 1, 4, 0, 1, 4, 6, 2, 4, 0, 3, 5, 1, 3, 6, 2, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4, 0, 3, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5, 1, 4, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6, 2, 5, 6, 2, 4, 0, 2, 5, 1

Offset

1,1

Comments

The index is 0-based, so 0 = Sunday, 1 = Monday, 2 = Tuesday, 3 = Wednesday, 4 = Thursday, 5 = Friday, 6 = Saturday.

The first term in the sequence represents the day of the week index for January 1, A.D. 2000.

The sequence repeats after 4800 terms, representing 400 years in the Gregorian calendar system.

References

Arthur Benjamin and Michael Shermer, Secrets of Mental Math, First Edition, Three Rivers Press, 2006, p. 215.

Links

Lyle P. Blosser, Table of n, a(n) for n = 1..4800

Index entries for sequences related to calendars

Formula

a(n+1) = (a(n) + A178055(n)) (mod 7).

Example

a(1) = 6, so day of week for January 1, 2000 is Saturday; a(2) = 2, so day of week for February 1, 2000 is Tuesday; a(3) = 3, so day of week for March 1, 2000 is Wednesday.

Crossrefs

Cf. A178055.

Sequence in context: A090425 A160081 A240937 * A195453 A259543 A256632

Adjacent sequences: A178051 A178052 A178053 * A178055 A178056 A178057

Keyword

easy,nonn

Author

Lyle P. Blosser (lyleblosser(AT)att.net), May 18 2010

Status

approved